18638944460 has 24 divisors (see below), whose sum is σ = 39145718976. Its totient is φ = 7454828160.

The previous prime is 18638944459. The next prime is 18638944507. The reversal of 18638944460 is 6444983681.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 185024 + ... + 267416.

It is an arithmetic number, because the mean of its divisors is an integer number (1631071624).

Almost surely, 2^18638944460 is an apocalyptic number.

18638944460 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18638944460 is an abundant number, since it is smaller than the sum of its proper divisors (20506774516).

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

18638944460 is a wasteful number, since it uses less digits than its factorization.

18638944460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93713 (or 93711 counting only the distinct ones).

The product of its (nonzero) digits is 3981312, while the sum is 53.

The spelling of 18638944460 in words is "eighteen billion, six hundred thirty-eight million, nine hundred forty-four thousand, four hundred sixty".