Project Euler Question 20 in Turkish: Sum of the Digits of a Factorial

Project Euler Question 20 in Turkish: Sum of the Digits of a Factorial

n! can be written as: n x (n-1) x … x 3 x 2 x 1

For example, 10! = 10 x 9 x … x 3 x 2 x 1 = 3628800.
And the sum of the digits of 10! is 3 + 6 + 2 + 8 + 8 = 27.

What is the sum of the digits of 100!?