What is the factorial of 20?

1 Answer
Dec 3, 2015

#20! = 20 xx 19 xx 18 xx ... xx 2 xx 1 = 2432902008176640000#

#~~ 2.4329 xx 10^18#

Explanation:

#n!# grows a little bit faster than #sqrt(n^n)#, but slower than #n^n#