252 is a composite number because it has factors other than 1 and itself. It is not a prime number. The 18 factors of 252 are 1, 2, 3, 4, 6, 7, 9, 12, 14, 18, 21, 28, 36, 42, 63, 84, 126, and 252. The factor pairs of 252 are 1 x 252, 2 x 126, 3 x 84, 4 x 63, 6 x 42, 7 x 36, 9 x 28, 12 x 21, and 14 x 18.