983

983 is a prime number.

983 is a number that cannot be written as a sum of three squares.

983 is the largest three-digit prime with distinct digits.

983 is a safe prime: a prime number of the form 2p + 1, where p is also a prime.

983 is the number of words in U.S. President Theodore Roosevelt's Inaugural Address, delivered March 4, 1905.

Source: Number Gossip