| Number: | 227 |
| Prime: | yes |
227 (two hundred [and] twenty-seven) is the natural number between 226 and 228. It is also a prime number.
227 is the 49th prime number, an index whose value is a square number (72). It is a twin prime, and the start of a prime triplet (with 229 and 233).
It is a safe prime, as dividing it by two and rounding down produces the Sophie Germain prime, 113. It is also:
227 and 229 form the first twin prime pair for which neither is a cluster prime.
The 227th harmonic number is the first to exceed 6.[1]
There are 227 different connected graphs with eight edges, and 227 independent sets in a 3 × 4 grid graph.
227 is the difference between 333 and 106, which are respectively the numerator and denominator in the fourth convergent to pi,[2] [3] correct to four decimal places:
\pi ≈
| 333 | |
| 106 |
≈ 3.1415{\color{red}0}\ldots