Prime Number Checker - Check if Number is Prime
Check if a number is prime and find its factors. Free online prime number checker and factorization tool.
Maximum: 10,000,000
How This Tool Works
This tool checks whether a number is prime (only divisible by 1 and itself) and finds all its factors and prime factors. A prime number has exactly two factors: 1 and itself. The tool uses an optimized algorithm to quickly check primality and factorize numbers up to 10 million.
Why Use This Tool
- ✓Check if numbers are prime instantly
- ✓Find all factors of a number
- ✓Get prime factorization
- ✓Perfect for math homework
- ✓Useful for cryptography learning
- ✓Handles numbers up to 10 million
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. Examples include 2, 3, 5, 7, 11, 13, etc. The number 1 is not considered prime.
What is prime factorization?
Prime factorization is expressing a number as a product of prime numbers. For example, 12 = 2 × 2 × 3. Every number has a unique prime factorization.
Why is 1 not a prime number?
By definition, a prime number must have exactly two distinct factors: 1 and itself. Since 1 only has one factor (itself), it doesn't meet the definition of a prime number.
What is the largest prime number?
There is no largest prime number - there are infinitely many primes. The largest known prime (as of 2024) has over 24 million digits! This tool can check numbers up to 10 million.
Why are prime numbers important?
Prime numbers are fundamental in mathematics and have practical applications in cryptography, computer science, and data security. RSA encryption, used for secure internet communication, relies on large prime numbers.