999319777

This number is a prime.

The largest 9-digit prime in a 156-digit number found by L. E. Card:

3 1 3 7 1 3 1 3 7 3 1 9 1 9 7 9 3 1 1 9 1 9 1 7 3 3 7 1 9 3 9 7 1 7 3 7 3 9 9 1 1 1 9 1 3 7 3 3 9 9 9 3 1 9 7 7 7 1 9 3 3 3 7 7 1 7 1 1 7 9 1 7 3 3 3 9 3 9 1 1 9 7 1 1 7 3 7 3 1 1 9 9 9 1 1 1 1 7 9 9 1 7 3 9 1 3 3 7 9 1 1 7 1 9 3 7 3 7 7 3 1 3 3 9 1 9 3 7 1 7 9 3 1 1 9 9 1 7 3 7 3 1 3 9 7 1 7 9 3 1 9 3 3 7 9 9.

There are a total of fifty-nine 9-digit primes within this number. [Patterson]