Prime
An integer greater than 1 with exactly two positive divisors: 1 and itself.
Number theory / visible working
BREAK A NUMBER
WIDE OPEN.
Check primality, expose every prime factor and divisor, find neighboring primes, then generate a whole range—all locally in your browser.
01 / INPUTinteger
Exact integer analysis is capped at one trillion to keep browser work responsive.
02 / RESULTtrial division
PRIME RANGE GENERATOR
Composite
An integer greater than 1 with more than two positive divisors. Its prime factorization is unique apart from factor order.
How we test
For one number the lab checks potential divisors only through its square root. Range generation uses the Sieve of Eratosthenes.