18009020 has 24 divisors (see below), whose sum is σ = 38212944. Its totient is φ = 7128576.

The previous prime is 18008993. The next prime is 18009031. The reversal of 18009020 is 2090081.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 18008983 and 18009001.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2702 + ... + 6581.

It is an arithmetic number, because the mean of its divisors is an integer number (1592206).

Almost surely, 2^18009020 is an apocalyptic number.

18009020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18009020 is an abundant number, since it is smaller than the sum of its proper divisors (20203924).

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

18009020 is a wasteful number, since it uses less digits than its factorization.

18009020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9389 (or 9387 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 18009020 is about 4243.7035711746. The cubic root of 18009020 is about 262.1179081984.

The spelling of 18009020 in words is "eighteen million, nine thousand, twenty".