The factor command in Linux is used to print the prime factors of the given numbers, either given from command line or read from standard input.
The numbers given through standard input may be delimited by tabs, spaces or newlines.
Factor 100(non-prime number):
We get the prime factors 2 and 5 that make up 100.
Factor 13(prime number itself) :
Factor of 221(product of two primes) :
Under the hood, the factor command uses the Pollard-Brent rho algorithm to find out the prime factors.
factor --help: This command only supports a few numbers of options, that is its help command and version number.