2537

This number is a composite.

2537 = 2^π(2)+5^π(5)+3^π(3)+7^π(7). Note that 2537 is the largest number with this property. [Firoozbakht]

The smallest of three brilliant numbers consisting of all the distinct prime digits, i.e., 2537=43*59. The other two are: 2573=31*83 and 5723=59*97. [Loungrides]