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Prime Number Checker
Check if a number is prime or find prime numbers in a range
Actions:
How to Use
1Enter a number to check
2View if it is prime or composite
3Find prime factors if not prime
4Generate primes in a range
Features
Single number prime check
Prime factorization
Range prime finder
Largest prime factor
Prime counting function
Benefits
Quickly verify prime numbers
Find prime factors for math problems
Generate prime number sequences
Frequently Asked Questions
What is a prime number?
A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself.
How large can numbers be checked?
The tool efficiently checks numbers up to 2^53 (about 9 quadrillion) using JavaScript's safe integer range.
Does it show prime factorization?
Yes. For composite numbers, the tool shows the complete prime factorization.