18005920 has 48 divisors (see below), whose sum is σ = 44785440. Its totient is φ = 6822144.

The previous prime is 18005909. The next prime is 18005927. The reversal of 18005920 is 2950081.

It is not an unprimeable number, because it can be changed into a prime (18005927) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79 + ... + 6001.

It is an arithmetic number, because the mean of its divisors is an integer number (933030).

Almost surely, 2^18005920 is an apocalyptic number.

18005920 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 18005920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22392720).

18005920 is an abundant number, since it is smaller than the sum of its proper divisors (26779520).

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

18005920 is a wasteful number, since it uses less digits than its factorization.

18005920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5957 (or 5949 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 18005920 is about 4243.3383084548. The cubic root of 18005920 is about 262.1028673625.

The spelling of 18005920 in words is "eighteen million, five thousand, nine hundred twenty".