Prime Number Checker

What is Prime Number Checker?

Instantly determine whether any number is prime. For composite numbers, see the complete prime factorization. Also generate lists of primes in any range, find the next/previous prime, and explore prime patterns — useful for math education, cryptography basics, and number theory.

How to use

1. Enter any positive integer to check if it's prime — results are instant even for large numbers.
2. For composite numbers, view the complete prime factorization tree. For primes, see the nearest primes above and below.
3. Use the range finder to list all primes between two numbers, or generate the first N primes.

Result

Enter 97 — it's prime! Enter 84 — not prime, factors are 2² × 3 × 7. Generate all primes between 1 and 100 to see all 25 primes in that range.

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