Prime Number Checker

Check if a number is prime and see its prime factorization.

Enter a number to check if it is prime

Prime Number Checker

A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself. Prime numbers are the building blocks of all natural numbers β€” every integer greater than 1 can be uniquely expressed as a product of primes, a result known as the Fundamental Theorem of Arithmetic.

This tool checks whether a given number is prime and, if it is not, shows its complete prime factorization. Understanding prime numbers is essential in number theory, cryptography, and computer science. They play a key role in encryption algorithms like RSA that secure modern internet communications.

How it works

A number n is prime if it has exactly two distinct divisors: 1 and n. Trial division checks divisibility by all integers from 2 up to √n. Prime factorization expresses n as a product of prime powers: n = p₁^a₁ Γ— pβ‚‚^aβ‚‚ Γ— ... Γ— pβ‚–^aβ‚–.

Use cases

  • Checking if a number is prime for math homework or competitions
  • Finding the prime factorization of composite numbers
  • Understanding number theory concepts like GCD and LCM
  • Learning about the building blocks of cryptographic algorithms

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