307

307 is a prime number.

307 is the smallest number that is the sum of any set of primes containing all digits: 2 + 5 + 41 + 67 + 83 + 109 = 307.

307² = 94249, which is a palindromic number.

307 is a prime of the form n² + n + 1, for n = 17.

307 is the telephone area code for the state of Wyoming.

Source: Number Gossip