91615680 has 168 divisors, whose sum is σ = 339498432. Its totient is φ = 22542336.

The previous prime is 91615679. The next prime is 91615687. The reversal of 91615680 is 8651619.

91615680 is a `hidden beast` number, since 91 + 6 + 1 + 568 + 0 = 666.

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 (91615687) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 36217 + ... + 38663.

It is an arithmetic number, because the mean of its divisors is an integer number (2020824).

Almost surely, 2^91615680 is an apocalyptic number.

91615680 is a gapful number since it is divisible by the number (90) 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 91615680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (169749216).

91615680 is an abundant number, since it is smaller than the sum of its proper divisors (247882752).

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

91615680 is a wasteful number, since it uses less digits than its factorization.

91615680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2483 (or 2470 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 91615680 is about 9571.6080153755. The cubic root of 91615680 is about 450.8062582801.

It can be divided in two parts, 9161 and 5680, that added together give a palindrome (14841).

The spelling of 91615680 in words is "ninety-one million, six hundred fifteen thousand, six hundred eighty".