251 (number)

251 is the natural number between 250 and 252. It is also a prime number.

List of numbers — Integers ← 0 100 200 300 400 500 600 700 800 900 →
Ordinal	Two hundred [and] fifty-one
Cardinal	251st
Factorization	prime number

In mathematics

251 is a regular prime, an Eisenstein prime, a Chen prime, a Gaussian prime, a Sophie Germain prime, and a sexy prime.

251 is also sum of three consecutive primes (79 + 83 + 89) and sum of seven consecutive primes (23 + 29 + 31 + 37 + 41 + 43 + 47).

251 is also the smallest number that can be written as the sum of three cubes in two ways: 251 = 1³ + 5³ + 5³ = 2³ + 3³ + 6³.

In other fields

• 2-5-1 is a common chord progression in jazz music.
• Vermont 251 Club is a club in which members try to visit each of the 251 towns and cities of Vermont.
• The number of Pokémon available in Pokémon Gold and Silver is 251
• 251 is a title of a play based on Annabel Chong story, who became famous for engaging in 251 sex acts over a ten hour period in January 1995, setting a world record as the world's biggest gang bang.
• The 251 is the last and most powerful prime mover (engine) designed and built by the American Locomotive Company (ALCO). It was available in 12- and 16-cylinder versions, along with a single experimental 18-cylinder variant. The 251 was produced from 1949 until ALCO left the locomotive business in 1969. The design is still currently produced by Fairbanks-Morse.