91665504 has 144 divisors (see below), whose sum is σ = 305454240. Its totient is φ = 25528320.

The previous prime is 91665503. The next prime is 91665521. The reversal of 91665504 is 40556619.

91665504 is a `hidden beast` number, since 91 + 6 + 65 + 504 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-3 number, since 3×91665504³ (a number of 25 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91665503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 82102 + ... + 83210.

It is an arithmetic number, because the mean of its divisors is an integer number (2121210).

Almost surely, 2^91665504 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 91665504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (152727120).

91665504 is an abundant number, since it is smaller than the sum of its proper divisors (213788736).

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

91665504 is a wasteful number, since it uses less digits than its factorization.

91665504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1173 (or 1162 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The square root of 91665504 is about 9574.2103590845. The cubic root of 91665504 is about 450.8879651834.

The spelling of 91665504 in words is "ninety-one million, six hundred sixty-five thousand, five hundred four".