Prime Number Checker
Check whether a natural number is prime and show its prime factorization when it is composite.
Category: Calculators
When to use?
Use it to verify whether 97 is prime, factor a number such as 360, or check number-theory homework and coding-test examples.
How to use
- Enter a natural number.
- Check whether it is prime, composite, or neither.
- If it is composite, review the prime factorization.
Input Explanation
Enter an integer of 2 or greater. The number 1 is neither prime nor composite.
Calculation Basis
The checker tests divisibility up to the square root of n, then divides by the smallest prime factors to build the factorization.
Usage Examples
- Math homework - Verify prime and factorization answers quickly.
- Cryptography learning - Explore the prime-number basics behind public-key cryptography.
Examples
- 97 is prime
- 360 = 2^3 × 3^2 × 5
- 221 = 13 × 17, so it is composite
FAQ
Is 1 a prime number?
No. A prime number has exactly two positive divisors, 1 and itself. The number 1 has only one positive divisor.
Is 2 prime?
Yes. It is the only even prime; every larger even number is divisible by 2.
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