18531903912 has 32 divisors (see below), whose sum is σ = 47824270080. Its totient is φ = 5978033280.

The previous prime is 18531903911. The next prime is 18531903931. The reversal of 18531903912 is 21930913581.

It is not an unprimeable number, because it can be changed into a prime (18531903911) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12453493 + ... + 12454980.

It is an arithmetic number, because the mean of its divisors is an integer number (1494508440).

Almost surely, 2^18531903912 is an apocalyptic number.

18531903912 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

18531903912 is an abundant number, since it is smaller than the sum of its proper divisors (29292366168).

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

18531903912 is a wasteful number, since it uses less digits than its factorization.

18531903912 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24908513 (or 24908509 counting only the distinct ones).

The product of its (nonzero) digits is 58320, while the sum is 42.

The spelling of 18531903912 in words is "eighteen billion, five hundred thirty-one million, nine hundred three thousand, nine hundred twelve".