Prime Number Checker
Check whether a number is prime, and see its prime factors if it isn't.
97 is a prime number.
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How It Works
Enter a whole number to check whether it's prime. Non-prime numbers show their prime factorization.
A prime number has exactly two divisors: 1 and itself
Example
97 is prime. 12 is not prime — it factors into 2 × 2 × 3.
Frequently Asked Questions
- Is 1 a prime number?
- No — by definition, a prime number has exactly two distinct divisors (1 and itself), but 1 has only one divisor, so it's neither prime nor composite.
- Is 2 the only even prime number?
- Yes — every other even number is divisible by 2, so it can't have exactly two divisors.
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