# What is 55 factorial ?

Steps to calculate factorial of 55

## How to calculate the factorial of 55

To find 55 factorial, or 55!, simply use the formula that multiplies the number 55 by all positive whole numbers less than it.

Let's look at how to calculate the Factorial of Fifty-five :

55! is exactly : 12696403353658275925965100847566516959580321051449436762275840000000000000

Factorial of 55 can be calculated as:
55! = 55 x 54 x 53 x 52 x ... x 3 x 2 x 1

The number of trailing zeros in 55! is 13

The number of digits in 55 factorial is 74.

## What Is Factorial?

A factorial is showed by an integer and an exclamation symbol. In arithmetic, factorial is a multiplication function of natural numbers .

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

Symbolically, it is listed as "!".

The function is used, among other things, to find the "n" way objects can be structured .

## Factorial Formula

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

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

The expansion of the formula shows the numbers to be multiplied together with each other to have the factorial of the number.

We can also figure out a factorial from the prior one. The factorial of any number is that number times the factorial of (that number minus 1).

So the rule is : n! = n × (n−1)!

Example :
55! Factorial = 55 x 54 x 53 x 52 x ... x 3 x 2 x 1 = 55 × 54! = 12696403353658275925965100847566516959580321051449436762275840000000000000

## 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 value is equal to 1. So, 0! = 1.