- Home ›
- Factorial ›
- Factorial of 20
Factorial of 20 is 2432902008176640000 | What is a factorial of 20 ?
How to calculate the factorial of 20
Lets check the detailed answer
20! is exactly: 2432902008176640000
The number of trailing zeros in 20! is 4.
The number of digits in 20 factorial is 19.
The factorial of 20 is 2432902008176640000 calculated, through its definition, this way:
20 X 19 X 18 X 17 X 16 X 15 X 14 X 13 X 12 X 11 X 10 X 9 X 8 X 7 X 6 X 5 X 4 X 3 X 2 X 1What is factorial of 20?
Definition of factorial of 20
The factorial is a basically a quantity which is defined for integer value 20 which is greater than or equal to 0.
The factorial is nothing but the product of all intergers which is less than or equal to n but it is greater than or equal to 1. By definition we can say that the factorial value of 0 is equal to 1. We can not have negative integers factorial as defined. We can see that factorial is the result of multiplying a sequence of descending natural numbers. We can say that factorial of 20 is calculated as 20 X 19 X 18 X 17 X 16 X 15 X 14 X 13 X 12 X 11 X 10 X 9 X 8 X 7 X 6 X 5 X 4 X 3 X 2 X 1
Factorial Formula for 20
For 20 is natural number which is greater than or equal to 1. Then we can have the formula as
20! = 20 x (20-1) X (20-2) X (20-3) X (20-4) X (20-5) X (20-6) X (20-7) X (20-8) X (20-9) X (20-10) X (20-11) X (20-12) X (20-13) X (20-14) X (20-15) X (20-16) X (20-17) X (20-18) X (20-19) X (20-20) ..... 20 X 19 X 18 X 17 X 16 X 15 X 14 X 13 X 12 X 11 X 10 X 9 X 8 X 7 X 6 X 5 X 4 X 3 X 2 X 1
Simalar Questions asked in exam for factorial of 20 :-
- Check How many digits are there in 20 factorial?
- What is the factorial of 20?
- How many trailing zeros are in 20 factorial?
- What is the last digits of factorial of 20?
Table for factorial of 1 to 20
| # | Factorial of | Factorial is |
|---|---|---|
| 1 | 1 | 1 |
| 2 | 2 | 2 |
| 3 | 3 | 6 |
| 4 | 4 | 24 |
| 5 | 5 | 120 |
| 6 | 6 | 720 |
| 7 | 7 | 5040 |
| 8 | 8 | 40320 |
| 9 | 9 | 362880 |
| 10 | 10 | 3628800 |
| 11 | 11 | 39916800 |
| 12 | 12 | 479001600 |
| 13 | 13 | 6227020800 |
| 14 | 14 | 87178291200 |
| 15 | 15 | 1307674368000 |
| 16 | 16 | 20922789888000 |
| 17 | 17 | 355687428096000 |
| 18 | 18 | 6402373705728000 |
| 19 | 19 | 121645100408832000 |
| 20 | 20 | 2432902008176640000 |
Factorial examples
Example 1:-
What is the factorial of 21?Solution :-
We know that factorial formula for 21 is21! = 21 × (21-1) X (21-2) X (21-3) X (21-4) X (21-5) X (21-6) X (21-7) X (21-8) X (21-9) X (21-10) X (21-11) X (21-12) X (21-13) X (21-14) X (21-15) X (21-16) X (21-17) X (21-18) X (21-19) X (21-20) X (21-21) ..... 21 X 20 X 19 X 18 X 17 X 16 X 15 X 14 X 13 X 12 X 11 X 10 X 9 X 8 X 7 X 6 X 5 X 4 X 3 X 2 X 1
So the factorial of 21 is
21! = 21 X (21-1) X (21-2) X (21-3) X (21-4) X (21-5) X (21-6) X (21-7) X (21-8) X (21-9) X (21-10) X (21-11) X (21-12) X (21-13) X (21-14) X (21-15) X (21-16) X (21-17) X (21-18) X (21-19) X (21-20) X (21-21)
21! = 21 X 20 X 19 X 18 X 17 X 16 X 15 X 14 X 13 X 12 X 11 X 10 X 9 X 8 X 7 X 6 X 5 X 4 X 3 X 2 X 1
21! = 51090942171709440000
Example 2:-
What is the factorial of 22?Solution :-
We know that factorial formula for 21 is22! = 22 × (22-1) X (22-2) X (22-3) X (22-4) X (22-5) X (22-6) X (22-7) X (22-8) X (22-9) X (22-10) X (22-11) X (22-12) X (22-13) X (22-14) X (22-15) X (22-16) X (22-17) X (22-18) X (22-19) X (22-20) X (22-21) X (22-22) ..... 22 X 21 X 20 X 19 X 18 X 17 X 16 X 15 X 14 X 13 X 12 X 11 X 10 X 9 X 8 X 7 X 6 X 5 X 4 X 3 X 2 X 1
So the factorial of 22 is
22! = 22 X (22-1) X (22-2) X (22-3) X (22-4) X (22-5) X (22-6) X (22-7) X (22-8) X (22-9) X (22-10) X (22-11) X (22-12) X (22-13) X (22-14) X (22-15) X (22-16) X (22-17) X (22-18) X (22-19) X (22-20) X (22-21) X (22-22)
22! = 22 X 21 X 20 X 19 X 18 X 17 X 16 X 15 X 14 X 13 X 12 X 11 X 10 X 9 X 8 X 7 X 6 X 5 X 4 X 3 X 2 X 1
22! = 1124000727777607680000
Example 3:-
What is the factorial of 23?Solution :-
We know that factorial formula for 23 is23! = 23 × (23-1) X (23-2) X (23-3) X (23-4) X (23-5) X (23-6) X (23-7) X (23-8) X (23-9) X (23-10) X (23-11) X (23-12) X (23-13) X (23-14) X (23-15) X (23-16) X (23-17) X (23-18) X (23-19) X (23-20) X (23-21) X (23-22) X (23-23) ..... 23 X 22 X 21 X 20 X 19 X 18 X 17 X 16 X 15 X 14 X 13 X 12 X 11 X 10 X 9 X 8 X 7 X 6 X 5 X 4 X 3 X 2 X 1
So the factorial of 23 is
23! = 23 X (23-1) X (23-2) X (23-3) X (23-4) X (23-5) X (23-6) X (23-7) X (23-8) X (23-9) X (23-10) X (23-11) X (23-12) X (23-13) X (23-14) X (23-15) X (23-16) X (23-17) X (23-18) X (23-19) X (23-20) X (23-21) X (23-22) X (23-23)
23! = 23 X 22 X 21 X 20 X 19 X 18 X 17 X 16 X 15 X 14 X 13 X 12 X 11 X 10 X 9 X 8 X 7 X 6 X 5 X 4 X 3 X 2 X 1
23! = 25852016738884976640000
Frequently Asked Questions(FAQ) for Factorial
What is the factorial of 20?
Click here for detailed step by step calculation for factorial of 20.
Check How many digits are there in 20 factorial?
The number of number of digits in 20 factorial is 19.
What is the meaning of 20 factorial?
What is the symbol of factorial?
The symbol for factorial is ! (exclamation mark).
What is the factorial of 0?
The value of factorial of 0 is 1, i.e. 0! = 1.
What is the factorial of 19?
The value of factorial of 19 is 121645100408832000.
What is the factorial of 23?
The value of factorial of 23 is 25852016738884976640000.
What is the factorial of 22?
The value of factorial of 22 is 1124000727777607680000.