91516581408 has 192 divisors, whose sum is σ = 277189032960. Its totient is φ = 25897190400.

The previous prime is 91516581391. The next prime is 91516581433. The reversal of 91516581408 is 80418561519.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 50532823 + ... + 50534633.

It is an arithmetic number, because the mean of its divisors is an integer number (1443692880).

Almost surely, 2^91516581408 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91516581408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (138594516480).

91516581408 is an abundant number, since it is smaller than the sum of its proper divisors (185672451552).

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

91516581408 is a wasteful number, since it uses less digits than its factorization.

91516581408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2511 (or 2503 counting only the distinct ones).

The product of its (nonzero) digits is 345600, while the sum is 48.

The spelling of 91516581408 in words is "ninety-one billion, five hundred sixteen million, five hundred eighty-one thousand, four hundred eight".