# Prime number tester

## World's simplest math tool

Free online prime number tester. Just enter your number on the left and it will automatically get checked for primality. There are no ads, popups or nonsense, just an awesome primality checker. Enter a number – test its primality. Created by mathematicians for mathematicians.

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Prime number tester tool
What is a prime number tester?

This tool checks whether an integer is a prime number or not. You can test arbitrarily large values, as well as test many numbers at the same time. To perform primality testing on many integers just by entering each of them on a new line. You can output test results of all values, display only prime numbers, or print only composite one numbers. Mathabulous!

Prime number tester examples
Click to use

Check First Ten Positive Integers

In this example we run primality test on the first ten positive integers and display all the results. There are four primes and six composite numbers.

1
2
3
4
5
6
7
8
9
10

1 is not a prime
2 is a prime
3 is a prime
4 is not a prime
5 is a prime
6 is not a prime
7 is a prime
8 is not a prime
9 is not a prime
10 is not a prime

**Required options**

Display status of all numbers.

Primality Test of Random Numbers

This example checks random numbers and outputs a list of all prime values that it finds. Fun fact – probability that a random number is prime is 1/ln(n).

2267
38051
1311
3
1979
57653
932
167135
25
81492

2267
3
1979
57653

**Required options**

Display only a list of prime numbers.

Large Composite Values

In this example we check four ten-digit numbers for primality and display only composite numbers.

9871299709
2346574524
1231299709
5737596733

2346574524
5737596733

**Required options**

Display only a list of composite numbers.

Pro tips
Master online math tools

You can pass input to this tool via

__?input__query argument and it will automatically compute output. Here's how to type it in your browser's address bar. Click to try!
https://onlinemathtools.com/test-prime-number

__?input__=1%0A2%0A3%0A4%0A5%0A6%0A7%0A8%0A9%0A10&test-all-numbers=true
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Calculate the n-th digit of Euler's number.

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Calculate the n-th digit of Golden Ratio.

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Calculate the n-th digit of pi constant.

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Perform the inverse operation on a look-and-say sequence.

Generate Stanley Number Sequence

Create a list of Stanley numbers.

Generate Bell Number Sequence

Create a list of Bell numbers.

Generate Carmichael Number Sequence

Create a list of Charmichel numbers.

Generate Catalan Number Sequence

Create a list of Catalan numbers.

Generate Composite Number Sequence

Create a list of composite numbers.

Generate Secant Number Sequence

Create a list of secant numbers.

Generate Golomb Number Sequence

Create a list of Golomb-Silverman numbers.

Generate Euler's Totient Number Sequence

Create a list of Euler's phi numbers.

Generate Juggler Number Sequence

Create a list of juggler numbers.

Generate Lucky Number Sequence

Create a list of lucky numbers.

Generate Motzkin Number Sequence

Create a list of motzkin numbers.

Generate Padovan Number Sequence

Create a list of Padovan numbers.

Generate Pseudoperfect Number Sequence

Create a list of semiperfect numbers.

Generate Ulam Number Sequence

Create a list of Ulam numbers.

Generate Weird Number Sequence

Create a list of weird numbers.

Generate Superperfect Number Sequence

Create a list of superperfect numbers.

Partition a Number

Find all partitions of the given integer.

Generate Partition Number Sequence

Create a list of Partition function numbers.

Generate Arithmetic Progression

Create an arithmetic sequence of numbers.

Generate Geometric Progression

Create a geometric sequence of numbers.

Generate Natural Number Sequence

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Generate Powers of Two

Create a list of numbers of powers of two.

Generate Powers of Ten

Create a list of numbers of powers of ten.

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