991288130023 has 8 divisors (see below), whose sum is σ = 1012723971840. Its totient is φ = 969866646840.

The previous prime is 991288130009. The next prime is 991288130039. The reversal of 991288130023 is 320031882199.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-991288130023 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991288130093) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3450033 + ... + 3726298.

It is an arithmetic number, because the mean of its divisors is an integer number (126590496480).

Almost surely, 2^991288130023 is an apocalyptic number.

991288130023 is a deficient number, since it is larger than the sum of its proper divisors (21435841817).

991288130023 is a wasteful number, since it uses less digits than its factorization.

991288130023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7179317.

The product of its (nonzero) digits is 186624, while the sum is 46.

The spelling of 991288130023 in words is "nine hundred ninety-one billion, two hundred eighty-eight million, one hundred thirty thousand, twenty-three".