1931
This number is a prime.
The year Gödel's incompleteness theorems were published. Recall that Kurt Gödel (1906-1978) used prime numbers to encode each element of a logical statement. [La Haye]
Nineteen 19's followed by thirty-one 31's is a prime with exactly one hundred digits. [De Geest]
Jane Addams became the first American woman to be awarded the Nobel Peace Prize in 1931. [Green]
Star Trek actors William Shatner (aka Captain Kirk) and Leonard Nimoy (aka Spock) were both born in the third month of 1931. [Green]
Nevada legalizes gambling in 1931. [Green]
Until Major League Baseball changed rules in the prime year 1931, a ball that bounced into the stands was a unit (home run) rather than a prime (double). [Post]
(1931 and 3119) is the only pair of 4-digit primes formed by concatenating in order and reverse order two consecutive primes in the sequence of odd-digit primes. [Loungrides]
The only prime concatenated from a pair of double-digit primes of form (n^2-6, n^2+6), where n is a prime. [Loungrides]
1931 and 1933 are the smallest set of twin primes in which one is a Sophie Germain prime and the other a Honaker prime. [Gaydos]
The largest of only three mountain primes each concatenated from two double-digit primes. The other two are 1361, 1741. [Loungrides]
The Fields Medal was first proposed in 1931. [Jackson]