Math
Prime Number Calculator
Check if a number is prime, find its factors, and list prime numbers in a range.
Result
β
How It Works
Enter a number to check if it's prime and see its factors. Or enter a limit to generate all primes up to that number.
Example
Number: 17 β '17 is a prime number.' Limit: 20 β '2,3,5,7,11,13,17,19'
Frequently Asked Questions
What is the largest number I can check?
The tool works up to about 10,000,000, but very large numbers may be slow.
What are primes used for?
Cryptography, random number generation, hashing, and many other areas.