How many zeros are at the end of the number $236!$? Are there any special formulas or ways to solve this that would work for the factorial of any number?
Thanks, |-(<>)-| Tie Fighter
How many zeros at the end?
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number-theory
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1Yes, there are formulas. I'll just say here that you need to count how many factors of 5 divide $236!.$ – 2017-01-20
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0$\lfloor 236 /5 \rfloor = 47$ multiples of $5$; $\lfloor47/5\rfloor = 9$ multiples of $25$; $\lfloor9/5\rfloor = 1$ multiple of $125$ giving $47+9+1 = 57$ multiples of $5$ contributing to the value of $236!$, hence $57$ zeroes at the end. – 2017-01-20