839

839 is a prime number.

(839 - 8)⁸ + (839 - 3)³ + (839 - 9)⁹ is a prime.

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

839 has a base 5 representation (11324) that begins with its base 9 representation (1132).

839 is 31013 in base 4.

Charles the Fat, Holy Roman Emperor, was born in the year 839.

Source: Prime Curios!