91557888 has 52 divisors (see below), whose sum is σ = 244157328. Its totient is φ = 30515200.

The previous prime is 91557887. The next prime is 91557899. The reversal of 91557888 is 88875519.

It is a self number, because there is not a number n which added to its sum of digits gives 91557888.

It is not an unprimeable number, because it can be changed into a prime (91557883) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8563 + ... + 16013.

Almost surely, 2^91557888 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 91557888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (122078664).

91557888 is an abundant number, since it is smaller than the sum of its proper divisors (152599440).

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

91557888 is an equidigital number, since it uses as much as digits as its factorization.

91557888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7478 (or 7456 counting only the distinct ones).

The product of its digits is 806400, while the sum is 51.

The square root of 91557888 is about 9568.5886106573. The cubic root of 91557888 is about 450.7114474523.

The spelling of 91557888 in words is "ninety-one million, five hundred fifty-seven thousand, eight hundred eighty-eight".