91561536 has 112 divisors (see below), whose sum is σ = 293705280. Its totient is φ = 27740160.

The previous prime is 91561531. The next prime is 91561567. The reversal of 91561536 is 63516519.

91561536 is a `hidden beast` number, since 9 + 1 + 5 + 615 + 36 = 666.

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

It is a self number, because there is not a number n which added to its sum of digits gives 91561536.

It is not an unprimeable number, because it can be changed into a prime (91561531) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16600 + ... + 21416.

Almost surely, 2^91561536 is an apocalyptic number.

91561536 is a gapful number since it is divisible by the number (96) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91561536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (146852640).

91561536 is an abundant number, since it is smaller than the sum of its proper divisors (202143744).

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

91561536 is a wasteful number, since it uses less digits than its factorization.

91561536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4849 (or 4833 counting only the distinct ones).

The product of its digits is 24300, while the sum is 36.

The square root of 91561536 is about 9568.7792324831. The cubic root of 91561536 is about 450.7174333685.

The spelling of 91561536 in words is "ninety-one million, five hundred sixty-one thousand, five hundred thirty-six".