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Prime Number Checker

Check if a number is prime or composite

Enter a number to check if it's prime

About Prime Numbers

What are Prime Numbers?

A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself.

Properties:

  • Only divisible by 1 and itself
  • Always odd except for 2
  • Infinite in number
  • Fundamental building blocks of numbers

First 20 Prime Numbers:

2
3
5
7
11
13
17
19
23
29
31
37
41
43
47
53
59
61
67
71