37273

This number is a prime.

The smallest prime-digit prime that can be represented as the sum of a prime and its reversal in two different ways, 25121+12152 and 26111+11162, is palindromic. [Bajpai]

The smallest palindromic prime-digit prime formed by inserting a digit in between a pair of double-digit emirps. Note that inserting the same digit in between their reversals another palindromic prime, 73237, is produced. [Loungrides]

The bottom row of a palindromic prime pyramid (starting with 2) of step size 1 and height 3, where each palindromic prime p is the smallest p that contains p in the row above (see related sequence):

 2 
 727 
37273

[Honaker]