Prime Number Checker
Test whether a number is prime, break composite numbers into prime factors, and list the primes in any range.
Runs in your browser. Nothing is uploaded Free, no sign-up Works on mobile
Number to check
97 is a prime number
Next prime
101
List primes from
to
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97
How to use Prime Number Checker
- Enter a whole number.
- See whether it is prime, its factors and the next prime.
- Enter a range to list every prime in it.
Frequently asked questions
Is 1 a prime number?
No. A prime has exactly two distinct factors, 1 and itself. 1 has only one factor, so it is neither prime nor composite.
How many primes are there below 100?
There are 25 prime numbers below 100, starting 2, 3, 5, 7, 11 and ending with 97.
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