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Time Waster Challenge
By AMnu, 7 years ago, In English

What is the largest number less than 2^64 which has exactly 90 positive divisors ?

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7 years ago, # |
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You can find the divisors of 90. Subtract 1 from each of them. And try to assign those divisors-1 as powers to some primes so that the multiplication of assigned divisors = 90. Take an assignment, and find the number as prime1^(divisor1-1) * prime2^(divisor2-1) * ... Take the maximum of those numbers which are less than 2^64.

Good luck!

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    7 years ago, # ^ |
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    If only there is another faster way.

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