Factorial Calculator
Calculate the factorial (n!) of a non-negative integer
Enter Number
Enter a non-negative integer (0 - 170)
Instructions & Examples
What is a Factorial?
The factorial of a non-negative integer n, denoted as n!, is the product of all positive integers less than or equal to n.
n! = n × (n-1) × (n-2) × ... × 2 × 1
Special cases:
- 0! = 1 (by definition)
- 1! = 1
Examples:
5! = 120Try it
10! = 3,628,800Try it
15! = 1,307,674,368,000Try it
Applications:
- Combinations and permutations in mathematics
- Probability and statistics
- Algorithm analysis
- Number theory
Notes:
- Tool supports numbers from 0 to 170
- Results are calculated using BigInt to handle large numbers
- Calculation steps are only shown for numbers ≤ 20