How to tell MMA to transform a number to a factorial,Is there a native function?

I came across the need to transform a number into a factorial n, with positive integer n, I have searched in the MMA information but I can’t find anything like that.

I imagine an input, which verifies that it is a factorial, and if it is, prints the number in its n-form!

if there is no native function any idea how to implement it?

for example

6402373705728000=18!

51090942171709420000 does not correspond to a factorial.

How do you tell if a D&D book is 3.0 or 3.5?

I’m new to d20. I recently acquired a bunch of D&D books and I’m sure they are all either 3.0 or 3.5, but it doesn’t say in the book which version it is. How can I tell which version the book is?

For instance, I have “Complete Warrior – A Player’s Guide to Combat for All Classes”. It’s hard back, published in ’03. Is it 3.0 or 3.5?

Another example, I have “Sword and Fist – A Guidebook to Fighters and Monks”. Perfect Bound, published in ’01. Is it 3.0 or 3.5?

When a ysoki is holding items in his cheek pouches, can others tell if they have something in there?

The rules on ysoki cheek pouches are rather vague on whether objects held inside them are actually concealed. It seems possible that someone else would be able to determine that the ysoki was concealing something either by visible bulge or by the impact the object has on the ysoki’s speech. Is there any published Starfinder source that addresses this question? If not, is there anything about rodent biology that suggests a good ruling?

How to tell a friend that they are the problem?

I know of a person who often rants in the server I am in about how every group he joins is terrible but from what he tells me he usually plays a homebrew class,has a backstory far different than other players(He also insists he is original and other players are unoriginal but the other players think his character is unoriginal. ) The last homebrew class he played was a gunslinger that also deals with demons.

I can tell that he is genuine in his complaints but I believe that he is the problem. I feel like I should tell him but I am not sure how to do it without starting a fight or getting ignored. So my question is how should I do it?

How can you tell the distances by road between the settlements of Ten Towns in Icewind Dale?

I’ve read through Chapter 1 of Icewind Dale: Rime of the Frostmaiden and have not found any guidance on how to judge distances and travel times between the settlements of Ten Towns.

Other than a good old fashion ruler compared to the map scale, is there a quick way to determine the distances between the settlements of Ten Towns?