18168840 has 64 divisors (see below), whose sum is σ = 60566400. Its totient is φ = 4844736.

The previous prime is 18168823. The next prime is 18168851. The reversal of 18168840 is 4886181.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 18168795 and 18168804.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7332 + ... + 9491.

It is an arithmetic number, because the mean of its divisors is an integer number (946350).

Almost surely, 2^18168840 is an apocalyptic number.

18168840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18168840 is an abundant number, since it is smaller than the sum of its proper divisors (42397560).

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

18168840 is a wasteful number, since it uses less digits than its factorization.

18168840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16843 (or 16833 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 36.

The square root of 18168840 is about 4262.4922287319. The cubic root of 18168840 is about 262.8910091166.

The spelling of 18168840 in words is "eighteen million, one hundred sixty-eight thousand, eight hundred forty".