1223

This number is a prime.

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

The smallest prime (emirp) formed from a Pythagorean quadruple (1-2-2-3). It is also a left-truncatable prime. [Loungrides]

The smallest prime (emirp) obtained by concatenating an integer with the product and sum of its own digits. [Loungrides]

The larger of only two non-titanic primes p, that is the product of a repunit number and all truncations of itself plus two, i.e., 111*11*1+2. Note that the other such prime, 11*1+2, is also emirp. [Loungrides]