91115904 has 192 divisors, whose sum is σ = 278374320. Its totient is φ = 26357760.

The previous prime is 91115881. The next prime is 91115909. The reversal of 91115904 is 40951119.

It is a tau number, because it is divible by the number of its divisors (192).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91115909) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 1719142 + ... + 1719194.

Almost surely, 2^91115904 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 91115904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (139187160).

91115904 is an abundant number, since it is smaller than the sum of its proper divisors (187258416).

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

91115904 is a wasteful number, since it uses less digits than its factorization.

91115904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129 (or 106 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 30.

The square root of 91115904 is about 9545.4651012929. The cubic root of 91115904 is about 449.9850266623.

The spelling of 91115904 in words is "ninety-one million, one hundred fifteen thousand, nine hundred four".