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237 LearnersLast updated on October 8, 2025
Factorial of -1
What is the Factorial of -1?
The factorial of a number is typically represented with an exclamation mark (!) after it.
For non-negative integers n, the factorial is defined as: n! = n × (n - 1) × (n - 2) × ... × 3 × 2 × 1
However, factorials are not defined for negative numbers in standard mathematics.
Therefore, the factorial of -1 is undefined.
It is important to note that factorials are only applicable to non-negative integers, where 0! is defined as 1 by convention.
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Important Glossaries of Factorial of -1
- Factorial: The product of all positive integers less than or equal to a given positive integer, denoted by n!. The factorial of a negative number is undefined.
- Non-negative integers: Whole numbers that are greater than or equal to zero (0, 1, 2, 3, ...).
- Undefined: A term used in mathematics to describe a value that does not have a meaning within a given context.
- Zero factorial: Defined as 1, it is a special case in the factorial function.
- Negative numbers: Numbers less than zero, which do not have defined factorials.
Vikrant Sharma
About the Author
Vikrant is a passionate Mathematics teacher with over 5 years of teaching experience in both conventional and Vedic Maths. His student-focused approach combines clear concepts with motivation and encouragement, helping students build confidence and develo
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