91591456320 has 1680 divisors, whose sum is σ = 421149231360. Its totient is φ = 18477268992.

The previous prime is 91591456309. The next prime is 91591456321. The reversal of 91591456320 is 2365419519.

91591456320 is a `hidden beast` number, since 9 + 1 + 5 + 9 + 1 + 4 + 5 + 632 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1680).

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

It is not an unprimeable number, because it can be changed into a prime (91591456321) by changing a digit.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 889237389 + ... + 889237491.

Almost surely, 2^91591456320 is an apocalyptic number.

91591456320 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 91591456320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (210574615680).

91591456320 is an abundant number, since it is smaller than the sum of its proper divisors (329557775040).

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

91591456320 is a wasteful number, since it uses less digits than its factorization.

91591456320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 194 (or 162 counting only the distinct ones).

The product of its (nonzero) digits is 291600, while the sum is 45.

The spelling of 91591456320 in words is "ninety-one billion, five hundred ninety-one million, four hundred fifty-six thousand, three hundred twenty".