# What is 64 factorial ?

Steps to calculate factorial of 64

## How to calculate the factorial of 64

To find 64 factorial, or 64!, simply use the formula that multiplies the number 64 by all positive whole numbers less than it.

Let's look at how to calculate the Factorial of Sixty-four :

64! is exactly : 126886932185884164103433389335161480802865516174545192198801894375214704230400000000000000

Factorial of 64 can be calculated as:
64! = 64 x 63 x 62 x 61 x ... x 3 x 2 x 1

The number of trailing zeros in 64! is 15

The number of digits in 64 factorial is 90.

## What Is Factorial?

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

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

Symbolically, it is symbolized as "!".

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

## Factorial Formula

To find the factorial of any given number, exchange the exact value for n in the given solution :

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

The expansion of the formula gives the numbers to be replicated collectively to find the factorial of the number.

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

So the rule is : n! = n × (n−1)!

Example :
64! Factorial = 64 x 63 x 62 x 61 x ... x 3 x 2 x 1 = 64 × 63! = 126886932185884164103433389335161480802865516174545192198801894375214704230400000000000000

## 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 corresponding to 1. So, 0! = 1.