Is 57 Prime?

Check if 57 is a prime number. A prime number is only divisible by 1 and itself.

Result: ✗ NO — 57 is NOT a prime number

Step-by-Step Solution

Step 1 What is a Prime Number?

A prime number is a natural number greater than 1 that has exactly two factors: 1 and itself.

To check if 57 is prime, we need to verify that no number from 2 to √57 divides it evenly.

Step 2 Determine Testing Range

Since 57 is odd, we only need to check odd divisors.

We only need to test up to √57 ≈ 7.55, which rounds down to 7.

If 57 has a factor larger than √57, it must also have a corresponding factor smaller than √57.

Step 3 Test Odd Divisors

Testing: 3, 5, 7, ... up to 7

57 ÷ 3 = 19 (no remainder!)

We found that 3 divides 57 evenly!

Step 4 Conclusion

57 = 3 × 19

Since 57 has factors other than 1 and itself, 57 is NOT a prime number.