ソフィー・ジェルマン素数
It is a prime number, a Sophie Germain prime and the sum of three consecutive primes (293 + 307 + 311). It is an Eisenstein prime with no imaginary part and real part of the form 3"n" − 1. Since 913 is a semiprime, 911 is a Chen prime. It is also a centered decagonal number.