333

This number is a composite.

333¹²² + 122³³³ is prime. [Kulsha]

333!₂ - 2^333 is prime. [Firoozbakht]

333 = 101 + 11 + 2 + 3 + 41 + 5 + 61 + 7 + 83 + 19, where each term is the smallest prime containing 0, 1, 2, ..., and 9, respectively. [Poo Sung]

(There is one curio for this number that has not yet been approved by an editor.)