18991040112 has 80 divisors (see below), whose sum is σ = 59466908160. Its totient is φ = 5754859200.

The previous prime is 18991040093. The next prime is 18991040129. The reversal of 18991040112 is 21104019981.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 1993464 + ... + 2002967.

It is an arithmetic number, because the mean of its divisors is an integer number (743336352).

Almost surely, 2^18991040112 is an apocalyptic number.

18991040112 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

18991040112 is an abundant number, since it is smaller than the sum of its proper divisors (40475868048).

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

18991040112 is a wasteful number, since it uses less digits than its factorization.

18991040112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3996459 (or 3996447 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 36.

The spelling of 18991040112 in words is "eighteen billion, nine hundred ninety-one million, forty thousand, one hundred twelve".