441 is a composite number because it has factors other than 1 and itself. It is not a prime number. The 9 factors of 441 are 1, 3, 7, 9, 21, 49, 63, 147, and 441. It is a square number (21 x 21), so...
3 x 3 x 7 x 7 = 441
It is: 3, 3, 7 and 7
The prime factors of 441 are: 3, 7
The Prime Factors of 441 are 3, 7