18904633920 has 168 divisors, whose sum is σ = 65389109760. Its totient is φ = 5012935680.

The previous prime is 18904633849. The next prime is 18904633949. The reversal of 18904633920 is 2933640981.

It is a happy number.

18904633920 is a `hidden beast` number, since 1 + 8 + 9 + 0 + 4 + 633 + 9 + 2 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 497185 + ... + 533855.

Almost surely, 2^18904633920 is an apocalyptic number.

18904633920 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 18904633920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32694554880).

18904633920 is an abundant number, since it is smaller than the sum of its proper divisors (46484475840).

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

18904633920 is a wasteful number, since it uses less digits than its factorization.

18904633920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36873 (or 36860 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 45.

The spelling of 18904633920 in words is "eighteen billion, nine hundred four million, six hundred thirty-three thousand, nine hundred twenty".