Do Negative Numbers Have Factorials?

The factorials for real negative numbers may be defined by the integral equation, MathML. The factorials of negative real numbers are complex numbers. At negative integers the imaginary part of complex factorials is zero, and the factorials for -1, -2, -3, -4 are -1, 2, -6, 24 respectively.

Is there factorial for negative numbers?

As per the present concept, the factorials of real negative numbers, are complex numbers. The factorials of real negative integers have their imaginary part equal to zero, thus are real numbers.

Why is it not possible to have a negative factorial?

Explanation: One of the main practical uses of the factorial is to give you the number of ways to permute objects. You can't permute −2 objects because you can't have less than 0 objects!