# What is 17 factorial ?

Steps to calculate factorial of 17

## How to calculate the factorial of 17

To find 17 factorial, or 17!, simply use the formula that multiplies the number 17 by all positive whole numbers less than it.

Let's look at how to calculate the Factorial of Seventeen :

17! is exactly : 355687428096000

Factorial of 17 can be calculated as:
17! = 17 x 16 x 15 x 14 x ... x 3 x 2 x 1

The number of trailing zeros in 17! is 3

The number of digits in 17 factorial is 15.

## What Is Factorial?

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

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

Symbolically, it is represented as "!".

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

## Factorial Formula

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

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

The expansion of the formula provides the numbers to be multiplied to each other to find the factorial of the number.

We can also measure 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 :
17! Factorial = 17 x 16 x 15 x 14 x ... x 3 x 2 x 1 = 17 × 16! = 355687428096000

## 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 integer 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.