13331

This number is a prime.

Just showing those entries submitted by 'Silva': (Click here to show all)

The sum of the squares of three consecutive odd triangular numbers (45^2 + 55^2 + 91^2). Note the three 3's in the middle. [Silva]

The smallest expanded palindromic prime, i.e., a palindromic prime obtained from another by repeating its digits in order, each digit repeated d times. [Silva]