23373613

This number is a prime.

455238, 802086, 805482, 1325034, 1371894, 2241678, 2435162, 3074663, 5258927, 8593099, and 17151829 have concatenation of prime factors (with multiplicities) identical to 23373613. There are no other 8-digit primes which give the same or greater results than this. [Suzanna]