9991730460591 has 64 divisors (see below), whose sum is σ = 17098983498240. Its totient is φ = 5699104427520.

The previous prime is 9991730460587. The next prime is 9991730460623. The reversal of 9991730460591 is 1950640371999.

9991730460591 is a `hidden beast` number, since 9 + 9 + 9 + 1 + 7 + 30 + 4 + 6 + 0 + 591 = 666.

It is not a de Polignac number, because 9991730460591 - 2² = 9991730460587 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9991730460521) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 148624101 + ... + 148691313.

It is an arithmetic number, because the mean of its divisors is an integer number (267171617160).

Almost surely, 2^{9991730460591} is an apocalyptic number.

9991730460591 is a deficient number, since it is larger than the sum of its proper divisors (7107253037649).

9991730460591 is a wasteful number, since it uses less digits than its factorization.

9991730460591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96693 (or 96687 counting only the distinct ones).

The product of its (nonzero) digits is 16533720, while the sum is 63.

The spelling of 9991730460591 in words is "nine trillion, nine hundred ninety-one billion, seven hundred thirty million, four hundred sixty thousand, five hundred ninety-one".