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Problem 20 (a.k.a. Who knew how simple python could be?)

n! means n x (n - 1) ... 3 x 2 x 1

For example, 10! = 10 x 9 ... 3 x 2 x 1 = 3628800, and the sum of the digits in the number 10! is 3 + 6 + 2 + 8 + 8 + 0 + 0 = 27.

Find the sum of the digits in the number 100!

This literally took a minute to write-up in python:

import math

def problem_20(target):

        factorial_num = str(math.factorial(target))

        sum = 0

        for number in factorial_num:
                sum += int(number)
        
        return sum
        
print(problem_20(100))