91215855360 has 864 divisors, whose sum is σ = 377983936512. Its totient is φ = 19874119680.

The previous prime is 91215855307. The next prime is 91215855377. The reversal of 91215855360 is 6355851219.

91215855360 is a `hidden beast` number, since 9 + 1 + 2 + 1 + 585 + 5 + 3 + 60 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 155392987 + ... + 155393573.

It is an arithmetic number, because the mean of its divisors is an integer number (437481408).

Almost surely, 2^91215855360 is an apocalyptic number.

91215855360 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 91215855360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (188991968256).

91215855360 is an abundant number, since it is smaller than the sum of its proper divisors (286768081152).

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

91215855360 is a wasteful number, since it uses less digits than its factorization.

91215855360 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 709 (or 692 counting only the distinct ones).

The product of its (nonzero) digits is 324000, while the sum is 45.

The spelling of 91215855360 in words is "ninety-one billion, two hundred fifteen million, eight hundred fifty-five thousand, three hundred sixty".