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.
Factorials of Numbers similar to 18
What Is Factorial?
A factorial is showed by an integer and an exclamation mark. In Mathematics, factorial is a multiplication function of natural numbers .
It multiplies the number by every natural number that is less than it .
Symbolically, it is showed as "!".
The function is used, among other things, to get the "n" way elements can be organized .
Factorial Formula
To find the factorial of any given number, change 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 provides the numbers to be replicated together to find the factorial of the number.
We can also figure out a factorial from the prior 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"
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 equal to 1. So, 0! = 1.