Largest known prime number explained

The largest known prime number is, a number which has 24,862,048 digits when written in base 10. It was found via a computer volunteered by Patrick Laroche of the Great Internet Mersenne Prime Search (GIMPS) in 2018.[1]

A prime number is a natural number greater than 1 with no divisors other than 1 and itself. According to Euclid's theorem there are infinitely many prime numbers, so there is no largest prime.

Many of the largest known primes are Mersenne primes, numbers that are one less than a power of two, because they can utilize a specialized primality test that is faster than the general one., the six largest known primes are Mersenne primes.[2] The last seventeen record primes were Mersenne primes.[3] [4] The binary representation of any Mersenne prime is composed of all ones, since the binary form of 2k − 1 is simply k ones.[5]

Finding larger prime numbers is popularly understood to permit stronger encryption, yet this is incorrect.[6] [7]

Current record

The record is currently held by with 24,862,048 digits, found by GIMPS in December 2018.[8] The first and last 120 digits of its value are shown below:

, this prime has held the record for more than 5 years, longer than any other prime since M19937 (which held the record for 7 years from 1971 to 1978).

Prizes

There are several prizes offered by the Electronic Frontier Foundation (EFF) for record primes. A prime with one million digits was found in 1999, earning the discoverer a US$50,000 prize.[9] In 2008, a ten-million digit prime won a US$100,000 prize and a Cooperative Computing Award from the EFF.[10] Time called this prime the 29th top invention of 2008.[11]

Both of these primes were discovered through the Great Internet Mersenne Prime Search (GIMPS), which coordinates long-range search efforts among tens of thousands of computers and thousands of volunteers. The $50,000 prize went to the discoverer and the $100,000 prize went to GIMPS. GIMPS will split the US$150,000 prize for the first prime of over 100 million digits with the winning participant. A further US$250,000 prize is offered for the first prime with at least one billion digits.

GIMPS also offers a US$3,000 research discovery award for participants who discover a new Mersenne prime of less than 100 million digits.[12]

History of largest known prime numbers

The following table lists the progression of the largest known prime number in ascending order. Here is the Mersenne number with exponent p, where p is a prime number. The longest record-holder known was, which was the largest known prime for 144 years. No records are known prior to 1456.

NumberDecimal expansion
(partial for numbers > M1000)
DigitsYear foundDiscoverer
M138,19141456Anonymous
M17131,07161588Pietro Cataldi
M19524,28761588Pietro Cataldi

\tfrac{232+1}{641}

6,700,41771732Leonhard Euler?
Euler did not explicitly publish the primality of 6,700,417, but the techniques he had used to factorise 232 + 1 meant that he had already done most of the work needed to prove this, and some experts believe he knew of it.[13]
M312,147,483,647101772Leonhard Euler

\tfrac{1018+1}{1000001}

999,999,000,001121851Included (but question-marked) in a list of primes by Looff. Given his uncertainty, some do not include this as a record.

\tfrac{264+1}{274177}

67,280,421,310,721141855Thomas Clausen (but no proof was provided).-[M<sub>59</sub>/179951][3,203,431,780,337][13][1867]Landry. A record if the immediately preceding entry is excluded.-->
M127170,141,183,460,469,231,731,687,303,715,884,105,727391876Édouard Lucas

\tfrac{2148+1}{17}

20,988,936,657,440,586,486,151,264,256,610,222,593,863,921441951Aimé Ferrier with a mechanical calculator; the largest record not set by computer.
180×(M127)2+15210644015679228794060694325390955853335898483908056458352183851018372555735221791951J. C. P. Miller & D. J. Wheeler[14]
Using Cambridge's EDSAC computer
M52168647976601306097149819007990813932172694353001433054093944634591855431833976560521225596406614545549772963113914808580371219879997166438125740282911150571511571952Raphael M. Robinson
M6075311379928167670986895882065524686273295931177270319231994441382004035598608522427391625022652292856688893294862465010153465793376527072394095199787665873519438312708353932190317281271831952Raphael M. Robinson
M1279104079321946...7031687290873861952Raphael M. Robinson
M2203147597991521...6866977710076641952Raphael M. Robinson
M2281446087557183...4181328363516871952Raphael M. Robinson
M3217259117086013...3629093150719691957Hans Riesel
M4423285542542228...9026085806071,3321961Alexander Hurwitz
M9689478220278805...8262257541112,9171963Donald B. Gillies
M9941346088282490...8837894635512,9931963Donald B. Gillies
M11213281411201369...0876963921913,3761963Donald B. Gillies
M19937431542479738...0309680414716,0021971Bryant Tuckerman
M21701448679166119...3535118827516,5331978Laura A. Nickel and Landon Curt Noll[15]
M23209402874115778...5237792645116,9871979Landon Curt Noll
M44497854509824303...96101122867113,3951979David Slowinski and Harry L. Nelson
M86243536927995502...70943343820725,9621982David Slowinski
M132049512740276269...45573006131139,7511983David Slowinski
M216091746093103064...10381552844765,0501985David Slowinski

391581 x 2216193-1

148140632376...83638737715165,0871989A group, "Amdahl Six": John Brown, Landon Curt Noll, B. K. Parady, Gene Ward Smith, Joel F. Smith, Sergio E. Zarantonello.[16] [17]
Largest non-Mersenne prime that was the largest known prime when it was discovered.
M756839174135906820...328544677887227,8321992David Slowinski and Paul Gage
M859433129498125604...243500142591258,7161994David Slowinski and Paul Gage
M1257787412245773621...976089366527378,6321996David Slowinski and Paul Gage
M1398269814717564412...868451315711420,9211996GIMPS, Joel Armengaud
M2976221623340076248...743729201151895,9321997GIMPS, Gordon Spence
M3021377127411683030...973024694271909,5261998GIMPS, Roland Clarkson
M6972593437075744127...1429241937912,098,9601999GIMPS, Nayan Hajratwala
M13466917924947738006...4702562590714,053,9462001GIMPS, Michael Cameron
M20996011125976895450...7628556820476,320,4302003GIMPS, Michael Shafer
M24036583299410429404...8827339694077,235,7332004GIMPS, Josh Findley
M25964951122164630061...2805770772477,816,2302005GIMPS, Martin Nowak
M30402457315416475618...4116529438719,152,0522005GIMPS, University of Central Missouri professors Curtis Cooper and Steven Boone
M32582657124575026015...1540539678719,808,3582006GIMPS, Curtis Cooper and Steven Boone
M43112609316470269330...16669715251112,978,1892008GIMPS, Edson Smith
M57885161581887266232...07172428595117,425,1702013GIMPS, Curtis Cooper
M74207281300376418084...39108643635122,338,6182016GIMPS, Curtis Cooper
M77232917467333183359...06976217907123,249,4252017GIMPS, Jonathan Pace
M82589933148894445742...32521790259124,862,048 2018GIMPS, Patrick Laroche

GIMPS found the fifteen latest records (all of them Mersenne primes) on ordinary computers operated by participants around the world.

The twenty largest known prime numbers

A list of the 5,000 largest known primes is maintained by the PrimePages,[18] of which the twenty largest are listed below.[19]

Rank Number Discovered Digits Form Ref
1282589933 − 12018-12-0724,862,048Mersenne
2277232917 − 12017-12-2623,249,425Mersenne[20]
3274207281 − 12016-01-0722,338,618Mersenne[21]
4257885161 − 12013-01-2517,425,170Mersenne[22]
5243112609 − 12008-08-2312,978,189Mersenne[23]
6242643801 − 12009-06-0412,837,064Mersenne[24]
7Φ3(−5166931048576)2023-10-0211,981,518Generalized unique[25]
8Φ3(−4658591048576)2023-05-3111,887,192Generalized unique[26]
9237156667 − 12008-09-0611,185,272Mersenne
10232582657 − 12006-09-049,808,358Mersenne[27]
1110223 × 231172165 + 12016-10-319,383,761Proth[28]
12230402457 − 12005-12-159,152,052Mersenne[29]
13225964951 − 12005-02-187,816,230Mersenne[30]
14224036583 − 12004-05-157,235,733Mersenne[31]
1519637361048576 + 12022-09-246,598,776Generalized Fermat[32]
1619517341048576 + 12022-08-096,595,985Generalized Fermat[33]
17202705 × 221320516 + 12021-11-256,418,121Proth[34]
18220996011 − 12003-11-176,320,430Mersenne[35]
1910590941048576 + 12018-10-316,317,602Generalized Fermat[36]
203 × 220928756 − 12023-07-056,300,184Thabit[37]

See also

External links

Notes and References

  1. Web site: GIMPS Project Discovers Largest Known Prime Number: 282,589,933-1 . 21 December 2018 . Mersenne Research, Inc. . 21 December 2018 .
  2. Web site: The largest known primes – Database Search Output . Prime Pages . 19 March 2023.
  3. Web site: The Largest Known Prime by Year: A Brief History . Chris . Caldwell . Prime Pages . 19 March 2023.
  4. The last non-Mersenne to be the largest known prime, was 391,581 ⋅ 2216,193 − 1; see also The Largest Known Prime by year: A Brief History originally by Caldwell.
  5. Web site: Perfect Numbers. Penn State University. 6 October 2019. An interesting side note is about the binary representations of those numbers....
  6. News: McKinnon . Mika . January 4, 2018 . This Is the Largest Known Prime Number Yet . July 6, 2024 . Smithsonian.
  7. Web site: Johnston . Nathaniel . September 11, 2009 . No, Primes with Millions of Digits Are Not Useful for Cryptography . July 6, 2024 . njohnston.ca.
  8. Web site: GIMPS Project Discovers Largest Known Prime Number: 282,589,933-1 . 21 December 2018 . Mersenne Research, Inc. . 21 December 2018 .
  9. Electronic Frontier Foundation, Big Prime Nets Big Prize.
  10. Web site: Record 12-Million-Digit Prime Number Nets $100,000 Prize . October 14, 2009 . Electronic Frontier Foundation . . November 26, 2011 .
  11. News: Best Inventions of 2008 - 29. The 46th Mersenne Prime . https://web.archive.org/web/20081102044641/http://www.time.com/time/specials/packages/article/0,28804,1852747_1854195_1854157,00.html . dead . November 2, 2008 . Time . . January 17, 2012 . October 29, 2008.
  12. Web site: GIMPS by Mersenne Research, Inc. . 21 November 2022 . mersenne.org.
  13. Book: How Euler Did Even More. 9780883855843. Edward Sandifer. C.. 19 November 2014. The Mathematical Association of America .
  14. Miller . J. C. P. . J. C. P. Miller . 1951 . Large Prime Numbers . Nature . 168 . 4280 . 838 . 1951Natur.168..838M . 10.1038/168838b0.
  15. [Landon Curt Noll]
  16. Letters to the Editor . 2324686 . The American Mathematical Monthly . 1990 . 97 . 3 . 214–215 . 10.1080/00029890.1990.11995576 . Brown . John . Noll . Landon Curt . Parady . B. K. . Smith . Joel F. . Zarantonello . Sergio E. . Smith . Gene Ward . Robinson . Raphael M. . Andrews . George E. .
  17. https://t5k.org/bios/code.php?code=Z Proof-code: Z
  18. Web site: The Prime Database: The List of Largest Known Primes Home Page. t5k.org/primes. 19 March 2023.
  19. Web site: The Top Twenty: Largest Known Primes. 19 March 2023.
  20. Web site: GIMPS Project Discovers Largest Known Prime Number: 277,232,917-1. mersenne.org. Great Internet Mersenne Prime Search. 3 January 2018.
  21. Web site: GIMPS Project Discovers Largest Known Prime Number: 274,207,281-1. mersenne.org. Great Internet Mersenne Prime Search. 29 September 2017.
  22. Web site: GIMPS Discovers 48th Mersenne Prime, 257,885,161-1 is now the Largest Known Prime.. mersenne.org. Great Internet Mersenne Prime Search. 29 September 2017. 5 February 2013.
  23. Web site: GIMPS Discovers 45th and 46th Mersenne Primes, 243,112,609-1 is now the Largest Known Prime.. mersenne.org. Great Internet Mersenne Prime Search. 29 September 2017. 15 September 2008.
  24. Web site: GIMPS Discovers 47th Mersenne Prime, 242,643,801-1 is newest, but not the largest, known Mersenne Prime.. mersenne.org. Great Internet Mersenne Prime Search. 29 September 2017. 12 April 2009.
  25. Web site: PrimePage Primes: Phi(3, - 516693^1048576) . t5k.org.
  26. Web site: PrimePage Primes: Phi(3, - 465859^1048576) . t5k.org.
  27. Web site: GIMPS Discovers 44th Mersenne Prime, 232,582,657-1 is now the Largest Known Prime.. mersenne.org. Great Internet Mersenne Prime Search. 29 September 2017. 11 September 2006.
  28. Web site: PrimeGrid's Seventeen or Bust Subproject. primegrid.com. PrimeGrid. 30 September 2017.
  29. Web site: GIMPS Discovers 43rd Mersenne Prime, 230,402,457-1 is now the Largest Known Prime.. mersenne.org. Great Internet Mersenne Prime Search. 29 September 2017. 24 December 2005.
  30. Web site: GIMPS Discovers 42nd Mersenne Prime, 225,964,951-1 is now the Largest Known Prime.. mersenne.org. Great Internet Mersenne Prime Search. 29 September 2017. 27 February 2005.
  31. Web site: GIMPS Discovers 41st Mersenne Prime, 224,036,583-1 is now the Largest Known Prime.. mersenne.org. Great Internet Mersenne Prime Search. 29 September 2017. 28 May 2004.
  32. Web site: PrimeGrid's Generalized Fermat Prime Search. primegrid.com. PrimeGrid. 7 October 2022.
  33. Web site: PrimeGrid's Generalized Fermat Prime Search. primegrid.com. PrimeGrid. 17 September 2022.
  34. Web site: PrimeGrid's Extended Sierpinski Problem Prime Search. primegrid.com. PrimeGrid. 28 December 2021.
  35. Web site: GIMPS Discovers 40th Mersenne Prime, 220,996,011-1 is now the Largest Known Prime.. mersenne.org. Great Internet Mersenne Prime Search. 29 September 2017. 2 December 2003.
  36. Web site: PrimeGrid's Generalized Fermat Prime Search . 7 November 2018 . primegrid.com . PrimeGrid.
  37. Web site: PrimeGrid's 321 Prime Search . 17 July 2023 . primegrid.com . PrimeGrid.