# What is 31 factorial ?

Steps to calculate factorial of 31

## How to calculate the factorial of 31

To find 31 factorial, or 31!, simply use the formula that multiplies the number 31 by all positive whole numbers less than it.

Let's look at how to calculate the Factorial of Thirty-one :

31! is exactly : 8222838654177922817725562880000000

Factorial of 31 can be calculated as:
31! = 31 x 30 x 29 x 28 x ... x 3 x 2 x 1

The number of trailing zeros in 31! is 7

The number of digits in 31 factorial is 34.

## What Is Factorial?

A factorial is symbolized by an integer and an exclamation symbol. In math concepts, factorial is a multiplication process of natural numbers .

It multiplies the number by every organic number that is less than it .

Symbolically, it is displayed as "!".

The function is used, among other things, to get the "n" way items can be arranged .

## Factorial Formula

To find the factorial of any given number, change the value for n in the given way :

n! = n × (n-1) × (n-2) × (n-3) × ….× 3 × 2 × 1

The expansion of the formula provides numbers to be multiplied together to have the factorial of the number.

We can also calculate a factorial from the previous one. The factorial of any number is that number multiplied the factorial of (that number minus 1).

So the rule is : n! = n × (n−1)!

Example :
31! Factorial = 31 x 30 x 29 x 28 x ... x 3 x 2 x 1 = 31 × 30! = 8222838654177922817725562880000000

## What are Factorials Used For?

The best use of factorial is in Combinations and Permutations.

Example : Determine how to arrange letters without repeating?

There one way for 1 letter "a":
2 ways for two letters "ab": ab, ba.
There are 6 ways for 3 letters "abc": abc acb cab bac bca.
There are 24 ways for 1234 of the letters "abcd"

## Frequently Asked Questions on Factorial

### Can we have factorials for negative numbers ?

Negative number factorials are undefined

### What Is 0!

Zero factorial or Factorial of 0 is simple, and its own value is corresponding to 1. So, 0! = 1.