91320880 has 80 divisors (see below), whose sum is σ = 243895104. Its totient is φ = 31150080.

The previous prime is 91320877. The next prime is 91320907. The reversal of 91320880 is 8802319.

It is a tau number, because it is divible by the number of its divisors (80).

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, 175020 + ... + 175540.

Almost surely, 2^91320880 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 91320880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (121947552).

91320880 is an abundant number, since it is smaller than the sum of its proper divisors (152574224).

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

91320880 is a wasteful number, since it uses less digits than its factorization.

91320880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 854 (or 848 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 91320880 is about 9556.1958958573. The cubic root of 91320880 is about 450.3222054559.

The spelling of 91320880 in words is "ninety-one million, three hundred twenty thousand, eight hundred eighty".