91577878688 has 96 divisors (see below), whose sum is σ = 196161315840. Its totient is φ = 41943432960.

The previous prime is 91577878661. The next prime is 91577878699. The reversal of 91577878688 is 88687877519.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2352503 + ... + 2391113.

It is an arithmetic number, because the mean of its divisors is an integer number (2043347040).

Almost surely, 2^91577878688 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 91577878688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98080657920).

91577878688 is an abundant number, since it is smaller than the sum of its proper divisors (104583437152).

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

91577878688 is a wasteful number, since it uses less digits than its factorization.

91577878688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38770 (or 38762 counting only the distinct ones).

The product of its digits is 379330560, while the sum is 74.

The spelling of 91577878688 in words is "ninety-one billion, five hundred seventy-seven million, eight hundred seventy-eight thousand, six hundred eighty-eight".