81584228532 has 24 divisors (see below), whose sum is σ = 190787184000. Its totient is φ = 27134173696.

The previous prime is 81584228507. The next prime is 81584228543. The reversal of 81584228532 is 23582248518.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7565532 + ... + 7576307.

It is an arithmetic number, because the mean of its divisors is an integer number (7949466000).

Almost surely, 2^81584228532 is an apocalyptic number.

It is an amenable number.

81584228532 is an abundant number, since it is smaller than the sum of its proper divisors (109202955468).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81584228532 is a wasteful number, since it uses less digits than its factorization.

81584228532 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15142295 (or 15142293 counting only the distinct ones).

The product of its digits is 1228800, while the sum is 48.

The spelling of 81584228532 in words is "eighty-one billion, five hundred eighty-four million, two hundred twenty-eight thousand, five hundred thirty-two".