11266...40001 (44-digits)

This number is a prime.

                            1126 6013476217 9220067183 8025115351 0000640001

The product of the first 8 square triangular numbers plus 1 is prime. Note that the products of the first 1, 2, 3 and 5 such numbers plus 1 are primes too. Do you see the Fibonacci sequence? [Petrov]