What is 18 factorial ?

Steps to calculate factorial of 18

How to calculate the factorial of 18

To find 18 factorial, or 18!, simply use the formula that multiplies the number 18 by all positive whole numbers less than it.

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

18! is exactly : 6402373705728000

Factorial of 18 can be calculated as:
18! = 18 x 17 x 16 x 15 x ... x 3 x 2 x 1

The number of trailing zeros in 18! is 3

The number of digits in 18 factorial is 16.

What Is Factorial?

A factorial is displayed by an integer and an exclamation mark. In math concepts, factorial is a multiplication treatment of natural numbers .

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

Symbolically, it is symbolized as "!".

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

Factorial Formula

To find the factorial of any given number, alternate the exact value for n in the given rule :

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

The expansion of the formula gives the numbers to be replicated together to receive the factorial of the number.

We can also figure out 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 :
18! Factorial = 18 x 17 x 16 x 15 x ... x 3 x 2 x 1 = 18 × 17! = 6402373705728000

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"