91890656 has 96 divisors (see below), whose sum is σ = 217945728. Its totient is φ = 37578240.

The previous prime is 91890629. The next prime is 91890677. The reversal of 91890656 is 65609819.

It is a super-2 number, since 2×91890656² = 16887785320220672, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 196535 + ... + 197001.

It is an arithmetic number, because the mean of its divisors is an integer number (2270268).

Almost surely, 2^91890656 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91890656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108972864).

91890656 is an abundant number, since it is smaller than the sum of its proper divisors (126055072).

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

91890656 is a wasteful number, since it uses less digits than its factorization.

91890656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 544 (or 536 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 44.

The square root of 91890656 is about 9585.9614019669. The cubic root of 91890656 is about 451.2568255810.

The spelling of 91890656 in words is "ninety-one million, eight hundred ninety thousand, six hundred fifty-six".