91296640 has 64 divisors (see below), whose sum is σ = 225828000. Its totient is φ = 35252224.

The previous prime is 91296593. The next prime is 91296641. The reversal of 91296640 is 4669219.

It is a tau number, because it is divible by the number of its divisors (64).

It is a self number, because there is not a number n which added to its sum of digits gives 91296640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91296641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16101 + ... + 21019.

Almost surely, 2^91296640 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 91296640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112914000).

91296640 is an abundant number, since it is smaller than the sum of its proper divisors (134531360).

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

91296640 is a wasteful number, since it uses less digits than its factorization.

91296640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4967 (or 4955 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 37.

The square root of 91296640 is about 9554.9275245812. The cubic root of 91296640 is about 450.2823577737.

The spelling of 91296640 in words is "ninety-one million, two hundred ninety-six thousand, six hundred forty".