Forty-four is a repdigit and palindromic number in decimal.
It is the first member of the first cluster of two square-primes; of the form p2 × q, specifically 22 × 11 = 44 and 32 × 5 = 45.
Since the greatest prime factor of 442 + 1 = 1937 is 149 and thus more than 44 twice, 44 is a Størmer number.
44 is a tribonacci number, preceded by 7, 13, and 24, whose sum it equals.
[7] 44 four-dimensional crystallographic point groups of a total 227 contain dual enantiomorphs, or mirror images.