Factorial of a number in mathematics is the product of all the positive numbers less than or equal to a number. But there are no positive values less than zero so the data set cannot be arranged which counts as the possible combination of how data can be arranged (it cannot). Thus, 0! = 1.

Does zero have factorial?

A zero factorial is a mathematical expression for the number of ways to arrange a data set with no values in it, which equals one. ... The definition of the factorial states that 0! = 1.

What is the answer for 0 factorial?

The idea of the factorial (in simple terms) is used to compute the number of permutations (combinations) of arranging a set of n numbers. It can be said that an empty set can only be ordered one way, so 0! = 1.