Emirp Primes

An emirp (prime spelled backwards) is a prime number that results in a different prime when its decimal digits are reversed. The term reversible prime may be used to mean the same as emirp, but may also, ambiguously, include the palindromic primes. The emirps in base 12 are (using reversed two and three for ten and eleven, respectively)

There is a subset of emirps x, with mirror x , such that x is the yth prime, and x is the y th prime.

Source: en.wikipedia.org