Forty-six is a Wedderburn-Etherington number, an enneagonal number and a centered triangular number. It is the sum of the totient function for the first twelve integers. 46 is the largest even integer that can not be expressed as a sum of two abundant numbers.

46 is the 16th semiprime. 46 is the third semiprime with a semiprime aliquot sum. The aliquot sequence of 46 is (46,26,16,15,9,4,3,1,0).

Since it is possible to find sequences of 46 consecutive integers such that each inner member shares a factor with either the first or the last member, 46 is an Erdős–Woods number.

Forty-six is also:

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