18388408920 has 128 divisors (see below), whose sum is σ = 65787171840. Its totient is φ = 4020318720.

The previous prime is 18388408903. The next prime is 18388409003. The reversal of 18388408920 is 2980488381.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 456571 + ... + 495210.

It is an arithmetic number, because the mean of its divisors is an integer number (513962280).

Almost surely, 2^18388408920 is an apocalyptic number.

18388408920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18388408920 is an abundant number, since it is smaller than the sum of its proper divisors (47398762920).

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

18388408920 is a wasteful number, since it uses less digits than its factorization.

18388408920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 951825 (or 951821 counting only the distinct ones).

The product of its (nonzero) digits is 884736, while the sum is 51.

The spelling of 18388408920 in words is "eighteen billion, three hundred eighty-eight million, four hundred eight thousand, nine hundred twenty".