| Minorplanet: | yes |
| 11133 Kumotori | |
| Background: |
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| Discovered: | 2 December 1996 |
| Mpc Name: | (11133) Kumotori |
| Alt Names: | 1996 XY |
| Named After: | Mount Kumotori |
| Epoch: | 23 March 2018 (JD 2458200.5) |
| Uncertainty: | 0 |
| Observation Arc: | 28.27 yr (10,324 d) |
| Perihelion: | 2.6210 AU |
| Semimajor: | 2.7762 AU |
| Eccentricity: | 0.0559 |
| Period: | 4.63 yr (1,690 d) |
| Mean Motion: | / day |
| Inclination: | 10.689° |
| Asc Node: | 83.096° |
| Arg Peri: | 158.34° |
| Mean Diameter: | 8.96 km |
| Albedo: | 0.057 |
| Abs Magnitude: | 13.613.97 |
11133 Kumotori (provisional designation ) is a background asteroid from the central regions of the asteroid belt, approximately 9km (06miles) in diameter. It was discovered on 2 December 1996, by Japanese amateur astronomer Takao Kobayashi at his Ōizumi Observatory. The asteroid was named after Mount Kumotori near Tokyo. It has a rotation period of 4.6 hours.
Kumotori is a non-family asteroid from the main belt's background population. It orbits the Sun in the central main-belt at a distance of 2.6–2.9 AU once every 4 years and 8 months (1,690 days; semi-major axis of 2.786 AU). Its orbit has an eccentricity of 0.06 and an inclination of 11° with respect to the ecliptic. The asteroid was first observed at Palomar Observatory in March 1989. The body's observation arc begins with its official discovery observation at Oizumi.
Kumotori has been characterized as a rare L-type asteroid by Pan-STARRS survey. It is also assumed to be a carbonaceous C-type asteroid.
In April 2012, a rotational lightcurve of Kumotori was obtained from photometric observations in the R-band by astronomers at the Palomar Transient Factory in California. Lightcurve analysis gave a rotation period of 4.634 hours with a brightness amplitude of 0.33 magnitude .
The Collaborative Asteroid Lightcurve Link assumes an albedo for a carbonaceous asteroid of 0.057 and calculates a diameter of 8.96 kilometers based on an absolute magnitude of 13.97.
This minor planet was named after Mount Kumotori (雲取山 Kumotori-san). With an altitude of 2017m (6,617feet), it is the highest peak in the Tokyo metropolitan area, located at the boundary between Tokyo and Saitama and considered to be one of the 100 most celebrated mountains of Japan. The official naming citation was published by the Minor Planet Center on 9 November 2003 .