91544985 has 80 divisors (see below), whose sum is σ = 191664000. Its totient is φ = 41785632.

The previous prime is 91544977. The next prime is 91544989. The reversal of 91544985 is 58944519.

91544985 is a `hidden beast` number, since 9 + 154 + 498 + 5 = 666.

It is not a de Polignac number, because 91544985 - 2³ = 91544977 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 91544985.

It is not an unprimeable number, because it can be changed into a prime (91544989) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 138586 + ... + 139244.

It is an arithmetic number, because the mean of its divisors is an integer number (2395800).

Almost surely, 2^91544985 is an apocalyptic number.

It is an amenable number.

91544985 is an abundant number, since it is smaller than the sum of its proper divisors (100119015).

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

91544985 is an equidigital number, since it uses as much as digits as its factorization.

91544985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 697 (or 674 counting only the distinct ones).

The product of its digits is 259200, while the sum is 45.

The square root of 91544985 is about 9567.9143495330. The cubic root of 91544985 is about 450.6902739516.

It can be divided in two parts, 91544 and 985, that added together give a palindrome (92529).

The spelling of 91544985 in words is "ninety-one million, five hundred forty-four thousand, nine hundred eighty-five".