3719

This number is a prime.

The smallest emirp formed by using all end digits of multidigit primes. [Tough]

The largest of four emirps each formed from two double-digit primes. The others are 1723, 1753, and 1789. [Loungrides]

The Gregorian year will not fall one day behind until the year 3719. [Jackson]

There are are 3719 different ways to arrange the set of twelve pentominoes into a rectangle (6-by-10, 5-by-12, 4-by-15, or 3-by-20), counting up to rotations and reflections. [Nie]

Chebyshev's bias indicates that prime numbers up to n for any natural number n tend to end in 3 or 7 slightly more often than 1 or 9. [Nie]