91431520488 has 192 divisors, whose sum is σ = 308905833600. Its totient is φ = 23734909440.

The previous prime is 91431520487. The next prime is 91431520511. The reversal of 91431520488 is 88402513419.

91431520488 is a `hidden beast` number, since 9 + 1 + 43 + 1 + 520 + 4 + 88 = 666.

It is not an unprimeable number, because it can be changed into a prime (91431520487) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 12930618 + ... + 12937686.

It is an arithmetic number, because the mean of its divisors is an integer number (1608884550).

Almost surely, 2^91431520488 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 91431520488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (154452916800).

91431520488 is an abundant number, since it is smaller than the sum of its proper divisors (217474313112).

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

91431520488 is a wasteful number, since it uses less digits than its factorization.

91431520488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9432 (or 9425 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 45.

The spelling of 91431520488 in words is "ninety-one billion, four hundred thirty-one million, five hundred twenty thousand, four hundred eighty-eight".