91440168732 has 120 divisors (see below), whose sum is σ = 260877843072. Its totient is φ = 27698090400.

The previous prime is 91440168731. The next prime is 91440168737. The reversal of 91440168732 is 23786104419.

91440168732 is a `hidden beast` number, since 91 + 440 + 16 + 87 + 32 = 666.

It is a super-2 number, since 2×91440168732² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91440168731) by changing a digit.

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 39 ways as a sum of consecutive naturals, for example, 15646603 + ... + 15652445.

Almost surely, 2^91440168732 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 91440168732, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130438921536).

91440168732 is an abundant number, since it is smaller than the sum of its proper divisors (169437674340).

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

91440168732 is a wasteful number, since it uses less digits than its factorization.

91440168732 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10261 (or 10250 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 45.

The spelling of 91440168732 in words is "ninety-one billion, four hundred forty million, one hundred sixty-eight thousand, seven hundred thirty-two".