A factorial is simply a function that multiplies a given number by every number before it. The function is also used among other things, to find the number of ways “n” number of objects can be arranged.
In mathematics, there are n! ways to arrange n objects in sequence. The n! (! = factorial) gives us the number of ways in which n objects can be permuted or combinated.
Instead of calculating a factorial one digit at a time, this calculator will calculate factorial n! for you, n being any number. If you enter an integer, up to 4 digits long, you will get the long integer answer and also the scientific notation for large factorials.