As the number 6 is greater than 0, we can say that this is a positive integer. We know that for any natural number n, the factorial value of n is \[n!\] which is obtained by multiplying n with all the integers less than this number till 0. That is, \[n!=n\times n-1\times n-2\times ......\times ... More on vedantu.com

To calculate the factorial of a number, multiply it by all whole numbers below it.  For example, 5! = 5x4x3x2x1 = 120. One use of factorials is to find the number of permutations (orders).  For example, if 5 people run in a race, any of the 5 people can finish first, any of the 4 remaining people can finish second, any of the remaining 3 people can finish third, any of the 2 remaining people can finish fourth, and the last remaining person finishes last.  So there are 5! = 5x4x3x2x1 = 120 different possible race results. More on reddit.com

In this video i will teach you how to get the derivative of a factorial function in just 6 minutes. this neat trick can help with complicated… More on reddit.com

Imagine a shelf. On that shelf, put 3 cards: one that says 1. One that says 2. And one that says 3. Put them on the shelf in some order (e.g. 2,1,3). How many orderings are possible? 3! = 6, right? Exactly. That’s how many different ways my shelf could look different. Now imagine we had 1 card instead of 3. How many ways can the shelf look? It’ll look like this: ____ [ 1 ] ____ with just the one card with a 1 on it. That’s the only possibility for the shelf. 1 factorial is 1. Now imagine we, in fact, have 0 cards. What’s 0 factorial? How many different ways can the shelf look? Only one: ________. There is one way to order zero objects. The way that produces an empty shelf. More on reddit.com