Seventy-two is a pronic number, as it is the product of 8 and 9. [1] It is the smallest Achilles number, as it's a powerful number that is not itself a power. [2]72 is an abundant number. [3] With exactly twelve positive divisors, including 12 (one of only two sublime numbers), [4] 72 is also the twelfth member in the sequence of refactorable numbers. [5] As no smaller number has more than 12 ... More @Wikipedia
Hover over any link to get a description of the article. Please note that search keywords are sometimes hidden within the full article and don't appear in the description or title.