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PROJECT EULER · #0020

Factorial Digit Sum

Statement only · SolvedOriginal problem ↗

n! means n×(n1)××3×2×1.

For example, 10!=10×9××3×2×1=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!.

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