The first program here does just that, actually it only finds probable primes with java's built in test, but it works. The answer is 7427466391.com

It leads you to another page with a puzzle to find the next in the series: 7182818284, 8182845904, 8747135266, 7427466391,(?). The first is easily recognizable as the next 10 digits of e after 2, the next is another 10 digit sequence. The sequence is all 10 digit numbers whose digits sum to 49, the second program prints out that sequence, the next one is 5966290435.