81926920 has 32 divisors (see below), whose sum is σ = 192352320. Its totient is φ = 31345600.

The previous prime is 81926891. The next prime is 81926947. The reversal of 81926920 is 2962918.

It is a self number, because there is not a number n which added to its sum of digits gives 81926920.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43606 + ... + 45445.

It is an arithmetic number, because the mean of its divisors is an integer number (6011010).

Almost surely, 2^81926920 is an apocalyptic number.

It is an amenable number.

81926920 is an abundant number, since it is smaller than the sum of its proper divisors (110425400).

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

81926920 is a wasteful number, since it uses less digits than its factorization.

81926920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89085 (or 89081 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 81926920 is about 9051.3490707187. The cubic root of 81926920 is about 434.3190473277.

The spelling of 81926920 in words is "eighty-one million, nine hundred twenty-six thousand, nine hundred twenty".