An integer n > 1 for which some epsilon > 0 makes sigma(n)/n^(1+epsilon) maximal among all integers greater than 1.
The first few colossally abundant numbers are: 2, 6, 12, 60, 120, 360, 2520, 5040, 55440, 720720, …
10 of the first one million positive integers are colossally abundant.
Learn more about colossally abundant numbers on wikipedia.
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