Number Theory
8 tools
Prime checker
Is it prime? Exact for numbers up to .Prime factorisation
Primes, divisor count and sum, , , and every divisor in pairs.Mod calculator
Powers, inverses and orders modulo .Power cycle explorer
Watch the last digits of repeat.Euclid steps
GCD, LCM and Bézout, one line at a time.Base converter
Write a number in any base from 2 to 36.Residue tables
Squares, cubes and other powers mod at a glance.Chinese remainder
Combine congruences, or see exactly why they clash.