91788928 has 128 divisors (see below), whose sum is σ = 233049600. Its totient is φ = 34974720.

The previous prime is 91788911. The next prime is 91788941. The reversal of 91788928 is 82988719.

It is a tau number, because it is divible by the number of its divisors (128).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 660283 + ... + 660421.

It is an arithmetic number, because the mean of its divisors is an integer number (1820700).

Almost surely, 2^91788928 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 91788928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (116524800).

91788928 is an abundant number, since it is smaller than the sum of its proper divisors (141260672).

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

91788928 is a wasteful number, since it uses less digits than its factorization.

91788928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238 (or 226 counting only the distinct ones).

The product of its digits is 580608, while the sum is 52.

The square root of 91788928 is about 9580.6538399005. The cubic root of 91788928 is about 451.0902420685.

The spelling of 91788928 in words is "ninety-one million, seven hundred eighty-eight thousand, nine hundred twenty-eight".