91718975040 has 448 divisors, whose sum is σ = 363833468928. Its totient is φ = 19018137600.

The previous prime is 91718974981. The next prime is 91718975069. The reversal of 91718975040 is 4057981719.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (448).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 45607635 + ... + 45609645.

Almost surely, 2^91718975040 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 91718975040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (181916734464).

91718975040 is an abundant number, since it is smaller than the sum of its proper divisors (272114493888).

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

91718975040 is a wasteful number, since it uses less digits than its factorization.

91718975040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2666 (or 2656 counting only the distinct ones).

The product of its (nonzero) digits is 635040, while the sum is 51.

The spelling of 91718975040 in words is "ninety-one billion, seven hundred eighteen million, nine hundred seventy-five thousand, forty".