Prime Numbers
Check if a number is prime and look at its divisors.
What is a Prime Number?
In mathematics, aPrime NumberIt is a natural number greater than 1 that has exactly two divisors: the number 1 and itself. If a number has three or more divisors, it is called a composite number.
Famous Examples:
- The number 2:It is the only even number that is prime, as it can only be divided by 1 and 2.
- The number 7:It is prime, because if we try to divide by 2, 3, 4, 5, or 6, we will always have a remainder. It only divides by 1 and by 7.
- The number 9:It is NOT prime (it is composite). Although it is odd, it is divisible by 1, 3, and 9.
Modern internet encryption (like bank passwords and transactions) is entirely based on gigantic prime numbers. Our calculator can check if large numbers are prime in fractions of a second. If the number is composite, it will list the divisors for you.