18189433920 has 224 divisors, whose sum is σ = 66290635008. Its totient is φ = 4139384832.

The previous prime is 18189433907. The next prime is 18189433931. The reversal of 18189433920 is 2933498181.

It is a tau number, because it is divible by the number of its divisors (224).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 18189433920.

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, 1559952 + ... + 1571568.

Almost surely, 2^18189433920 is an apocalyptic number.

18189433920 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 18189433920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33145317504).

18189433920 is an abundant number, since it is smaller than the sum of its proper divisors (48101201088).

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

18189433920 is a wasteful number, since it uses less digits than its factorization.

18189433920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11877 (or 11867 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 48.

The spelling of 18189433920 in words is "eighteen billion, one hundred eighty-nine million, four hundred thirty-three thousand, nine hundred twenty".