What is 20 factorial ?

To find 20 factorial, or 20!, simply use the formula that multiplies the number 20 by all positive whole numbers less than it.

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

  20! is exactly : 2432902008176640000

  Factorial of 20 can be calculated as:
20! = 20 x 19 x 18 x 17 x ... x 3 x 2 x 1

  The number of trailing zeros in 20! is 4

  The number of digits in 20 factorial is 19.

• 16 Factorial
• 17 Factorial
• 18 Factorial
• 19 Factorial
• Factorial of 21
• Factorial of 22
• Factorial of 23
• Factorial of 24

A factorial is showed by an integer and an exclamation tag. In Mathematics, factorial is a multiplication operation 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 find the "n" way things can be determined .

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

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

The expansion of the formula provides numbers to be replicated together with each other to receive the factorial of the number.

We can also measure a factorial from the prior 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 :
20! Factorial = 20 x 19 x 18 x 17 x ... x 3 x 2 x 1 = 20 × 19! = 2432902008176640000

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"

1) Can we have factorials for negative numbers ?
  Negative integer factorials are undefined

2) What Is 0!
 Zero factorial or Factorial of 0 is simple, and its value is corresponding to 1. So, 0! = 1.

20 in French

20 in English

Factors of 20