5113

This number is a prime.

In 2005, Bobby Jacobs won the regional MATHCOUNTS competition in Richmond, Virginia, while wearing his favorite lucky shirt bearing the prime number 5113.

5113 can be written as a sum of positive squares in only one way.

The largest possible prime number found by using the digits 1 through 9 (in order) and the operators "*" and "+" between any digits, i.e., 1+2*3*4*5*6*7+8*9 = 5113. [Loungrides]