109139149179199

This number is a prime.

                                                            10913 9149179199

The ordered concatenation of all the 3-digit primes beginning with 1 and ending with 9, i.e., 109, 139, 149, 179, 199 is prime. Note that the concatenation of the same primes in descending order, i.e., 199179149139109 is also prime. [Loungrides]