1337 is a number with exactly two palindromic prime factors and no other prime factors (A046368).
1337 is the smallest number m such that reversal of m1000 is prime.
1337 is a multiple of 7 such that its digit sum (1 + 3 + 3 + 7 = 14) is divisible by 7 (A216994).
1337 is the product of two distinct primes a and b such that a + b is the average of a twin prime pair (A176875): 7 + 191 = 198 = (197 + 199)/2.
1337 is the average of three successive primes, each squared (A075893).
1337 is a multiple of 7 containing only odd digits (A061825).
1337 is a divisor of 3915 - 1.
1137 Gerarda is an asteroid discovered in 1934.
Leet (or "1337") is an alternative alphabet for the English language that is used mainly on the Internet.
Source: Number Gossip