91559559168 has 660 divisors, whose sum is σ = 347137293492. Its totient is φ = 23781703680.

The previous prime is 91559559167. The next prime is 91559559193. The reversal of 91559559168 is 86195595519.

91559559168 is a `hidden beast` number, since 9 + 15 + 5 + 9 + 559 + 1 + 68 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91559559163) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 8323596283 + ... + 8323596293.

Almost surely, 2^91559559168 is an apocalyptic number.

91559559168 is a gapful number since it is divisible by the number (98) 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 91559559168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (173568646746).

91559559168 is an abundant number, since it is smaller than the sum of its proper divisors (255577734324).

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

91559559168 is an frugal number, since it uses more digits than its factorization.

91559559168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79 (or 23 counting only the distinct ones).

The product of its digits is 21870000, while the sum is 63.

The spelling of 91559559168 in words is "ninety-one billion, five hundred fifty-nine million, five hundred fifty-nine thousand, one hundred sixty-eight".