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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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Numbers Check Options
Display status of all numbers.
Display only a list of prime numbers.
Display only a list of сomposite numbers.
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
These options will be used automatically if you select this example.
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
These options will be used automatically if you select this example.
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
These options will be used automatically if you select this example.
Display only a list of сomposite 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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Quickly visualize rules of an Lindenmayer rewrite system.
Quickly generate a list of primes.
Quickly generate a list of Fibonacci numbers.
Quickly generate a list of extended, negative Fibonacci numbers.
Quickly generate a list of Fibonacci primes.
Quickly generate a list of Fibonacci words.
Quickly generate a list of Tribonacci words.
Quickly generate a list of Lucas numbers.
Quickly generate a list of extended, negative Lucas numbers.
Quickly generate a list of Lucas numbers that are also prime numbers.
Quickly create a list of excessive numbers.
Quickly create a list of deficient numbers.
Quickly generate a list of perfect numbers.
Quickly create a list of slightly defective numbers.
Quickly generate random numbers.
Quickly generate a list of look-and-say sequence numbers.
Quickly create a list of Prouhet-Thue-Morse sequence values.
Quickly create a list of dragon curve sequence values.
Quickly create a list of Oldenburger-Kolakoski sequence values.
Quickly create a list of Gijswijt sequence values.
Quickly create a list of Golay-Rudin-Shapiro sequence values.
Quickly create a list of Baum-Sweet sequence values.
Quickly create a list of Moser-de Bruijn sequence values.
Quickly generate a list of even numbers.
Quickly generate a list of odd numbers.
Quickly find all factors of the given integer.
Quickly decompose integers into their prime factors.
Quickly find out if the given integer is a prime number.
Quickly check if the given number is a Fibonacci number
Quickly generate π constant's digits to arbitrary precision.
Quickly calculate Euler constant's digits to arbitrary precision.
Quickly calculate φ constant's digits to arbitrary precision.
Quickly calculate factorials.
Quickly create a triangluar array of binomial coefficients.
Quickly create a matrix with random elements.
Quickly create a unit matrix with ones along the diagonal.
Quickly find the transpose of a matrix.
Quickly find the inverse of a matrix.
Quickly calculate the determinant of a matrix.
Quickly find the sum of two or more matrices.
Find the difference of two or more matrices.
Quickly find the product of matrices.
Quickly draw a Hilbert space-filling curve.
Quickly draw a Heighway triangle fractal.
Quickly draw a Harter-Heighway space-filling dragon fractal.
Quickly draw a Davis-Knuth dragon fractal.
Quickly draw a triple dragon fractal.
Quickly draw a quaddragon fractal.
Quickly draw a hexdragon curve.
Quickly draw a Peano space-filling fractal.
Quickly draw a Moore space-filling curve.
Quickly draw a Peano-Gosper space-filling curve.
Quickly draw a Sierpinski arrowhead fractal curve.
Quickly draw a Sierpinski sieve fractal.
Quickly draw a Sierpinski closed plane fractal curve.
Quickly draw a Sierpinski carpet fractal.
Quickly draw a Sierpinski maze fractal.
Quickly draw a Sierpinski square fractal.
Quickly draw a Sierpinski pentaflake fractal.
Quickly draw a Sierpinski hexaflake fractal.
Quickly draw a Sierpinski n-gon fractal.
Quickly draw a Koch island fractal curve.
Quickly draw a Koch antisnowflake fractal.
Quickly draw a Koch triangle fractal.
Quickly draw a Koch n-gon fractal.
Quickly draw a quadratic Koch flake fractal.
Quickly draw a Cesaro fractal.
Quickly draw a Cesaro n-gon fractal.
Quickly draw a triflake fractal.
Quickly draw a quadric cross fractal.
Quickly draw a self-similar Levy C fractal curve.
Quickly draw a Vicsek snowflake fractal.
Quickly draw a T-square fractal.
Quickly draw a Cantor set fractal.
Quickly draw an asymmetric Cantor set fractal.
Quickly draw a generalized Cantor set fractal.
Quickly draw an ε-Cantor set fractal.
Quickly draw a Cantor dust fractal.
Quickly draw a Pythagoras tree fractal.
Quickly draw a Fibonacci word fractal.
Quickly draw an H-tree fractal.
Quickly draw a V-tree fractal.
Quickly generate a Morton Z-order fractal curve.
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Find n-th e Digit
Calculate the n-th digit of Euler's number.
Find n-th Golden Ratio Digit
Calculate the n-th digit of Golden Ratio.
Find n-th Pi Digit
Calculate the n-th digit of pi constant.
Decode a Look-and-say Sequence
Perform the inverse operation on a look-and-say sequence.
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
Create a list of natural numbers.
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.
Multiply a Matrix by a Scalar
Multiply all matrix elements by a number.
Check if a Matrix is Singular
Determine if a matrix is degenerate.
Find the Co-factor Matrix
Given a matrix, find its cofactor matrix.
Find the Adjugate Matrix
Given a matrix, find its adjunct.
LU Factor a Matrix
Decompose a matrix into LU factors.
Find Matrix Eigenvalues
Find eigenvalues of a matrix.
Prettify a Matrix
Beautify a matrix by neatly aligning all its columns.
Reformat a Matrix
Convert matrix in one format to another format.
Draw a Fibonacci Spiral
Generate a Fibonacci spiral curve.
Draw Fibonacci Rectangles
Generate a drawing of Fibonacci rectangles.
Draw a Fibonacci Seed Head
Generate a Fibonacci flower head.
Draw a Padovan Fractal
Generate a Padovan equiliteral triangles fractal.
Draw a Apollonian Gasket
Generate an Apollonian gasket fractal.
Draw a Mandelbrot Fractal
Generate a Mandelbrot fractal.
Draw a Julia Fractal
Generate a Julia fractal.
Draw a Rauzy Fractal
Generate a Rauzy fractal.
Draw Blancmange Fractal Curve
Generate a Blancmange fractal.
Draw Weierstrass Function
Generate a Weierstrass fractal.
Draw Minkowski Question-mark Curve
Generate a Minkowski Question-mark fractal.
Draw Thomae's Function
Generate a Thomae's function (also known as popcorn or raindrop function).
Draw Dirichlet's Function
Generate a Dirichlet's function.
Convert Words to Numbers
Convert numbers as English text to actual digits.
Convert Numbers to Words
Convert numbers to written English text.
Convert Decimal Notation to Scientific Notation
Convert numbers written in decimal form to scientific form.
Convert Scientific Notation to Decimal Notation
Convert numbers written in scientific form to decimal form.
Round Numbers Up
Apply ceil operation to numbers.
Round Numbers Down
Apply floor operation to numbers.