91019

This number is a prime.

91019 = 100019 - 10009 + 1009 is a palindromic prime whose digits are not prime. Note that 1009, 10009 and 100019 are the smallest four, five and six-digit primes whose digits are not prime. [Gevisier]

9/10/19 will be the next (and largest) palindromic prime date of form MDDYY. Curiously, it falls on the eve of 911. [Gupta]

The smallest palindromic Cyclops Honaker prime. [Gaydos]

The smallest palindromic prime of form PSn formed by concatenating in order the product P of the digits of a double-digit prime n, the sum S of the digits and the number n, case, (n=19), i.e., P=9, S=10. [Loungrides]