991236328924 has 48 divisors (see below), whose sum is σ = 1819946953440. Its totient is φ = 471909231360.

The previous prime is 991236328921. The next prime is 991236328931. The reversal of 991236328924 is 429823632199.

991236328924 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991236328921) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1499847 + ... + 2057185.

It is an arithmetic number, because the mean of its divisors is an integer number (37915561530).

Almost surely, 2^991236328924 is an apocalyptic number.

It is an amenable number.

991236328924 is a deficient number, since it is larger than the sum of its proper divisors (828710624516).

991236328924 is a wasteful number, since it uses less digits than its factorization.

991236328924 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 557638 (or 557636 counting only the distinct ones).

The product of its digits is 10077696, while the sum is 58.

The spelling of 991236328924 in words is "nine hundred ninety-one billion, two hundred thirty-six million, three hundred twenty-eight thousand, nine hundred twenty-four".