Most people can tell just by looking that **443** cannot be evenly divided by 2, 3, or 5. Could it possibly be a prime number? Scroll down past the puzzle to know for sure.

Print the puzzles or type the factors on this excel file: 10 Factors 2015-03-30

- 443 is a prime number.
- Prime factorization: 443 is prime.
- The exponent of prime number 443 is 1. Adding 1 to that exponent we get (1 + 1) = 2. Therefore 443 has exactly 2 factors.
- Factors of 443: 1, 443
- Factor pairs: 443 = 1 x 443
- 443 has no square factors that allow its square root to be simplified. √443 ≈ 21.0476

**How do we know that ****443**** is a prime number?** If 443 were not a prime number, then it would be divisible by at least one prime number less than or equal to √443 ≈ 21.0476. Since 443 cannot be divided evenly by 2, 3, 5, 7, 11, 13, 17, or 19, we know that 443 is a prime number.