1213

This number is a prime.

The smallest four-digit prime (emirp) containing consecutive numbers (12 and 13). [Das]

12 and 13 are relatively prime, while 12^2 + 13^2 = 313 (a palindromic prime). Note also that 12^4 + 13^4 = 49297 is prime. [La Haye]

The smallest of eight consecutive emirps. [Punches]

The smallest emirp whose product of digits is a perfect number. [Loungrides]

The only emirp concatenated from two double-digit numbers that are sides in an equable triangle, i.e., (5, 12, 13). (A shape is called equable if its area equals the perimeter). [Loungrides]

Only non-titanic emirp, that is the product of a repunit number and all its truncations minus eight, i.e., 111*11*1-8. [Gupta]