18338785920 has 768 divisors, whose sum is σ = 79394515200. Its totient is φ = 3797286912.

The previous prime is 18338785859. The next prime is 18338785951. The reversal of 18338785920 is 2958783381.

18338785920 is a `hidden beast` number, since 18 + 3 + 38 + 7 + 8 + 592 + 0 = 666.

It is a super-2 number, since 2×18338785920² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 30925144 + ... + 30925736.

It is an arithmetic number, because the mean of its divisors is an integer number (103378275).

Almost surely, 2^18338785920 is an apocalyptic number.

18338785920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18338785920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39697257600).

18338785920 is an abundant number, since it is smaller than the sum of its proper divisors (61055729280).

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

18338785920 is a wasteful number, since it uses less digits than its factorization.

18338785920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 697 (or 682 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 54.

The spelling of 18338785920 in words is "eighteen billion, three hundred thirty-eight million, seven hundred eighty-five thousand, nine hundred twenty".