43912...44001 (24-digits)

This number is a prime.

                                                  4391 2023255647 9427744001

The product of the first fifteen terms of the Fibonacci-like sequence 3, 1, 4, 5, 9, 14, 23, 37, 60, 97, 157, 254, 411, 665, 1076, etc. plus one is prime. Note that 3 * 1 * 4 * 5 * 9 * 14 * 23 * 37 * 60 * 97 * 157 * 254 * 411 * 665 * 1076 + 1 = 439120232556479427744001 which is prime. One might call this sequence the Reverse Lucas sequence; for the first two terms are 3 and 1 respectively instead of 1 and 3 in the case of the classical Lucas sequence. [Schiffman]