18090018 has 24 divisors (see below), whose sum is σ = 40030848. Its totient is φ = 5901432.

The previous prime is 18090001. The next prime is 18090031. The reversal of 18090018 is 81009081.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 18089973 and 18090000.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9846 + ... + 11537.

It is an arithmetic number, because the mean of its divisors is an integer number (1667952).

Almost surely, 2^18090018 is an apocalyptic number.

18090018 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

18090018 is an abundant number, since it is smaller than the sum of its proper divisors (21940830).

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

18090018 is a wasteful number, since it uses less digits than its factorization.

18090018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21438 (or 21435 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 27.

The square root of 18090018 is about 4253.2361796637. The cubic root of 18090018 is about 262.5102907530.

Adding to 18090018 its reverse (81009081), we get a palindrome (99099099).

The spelling of 18090018 in words is "eighteen million, ninety thousand, eighteen".