18168818 has 16 divisors (see below), whose sum is σ = 29117880. Its totient is φ = 8472576.

The previous prime is 18168817. The next prime is 18168823. The reversal of 18168818 is 81886181.

It can be written as a sum of positive squares in 4 ways, for example, as 7166329 + 11002489 = 2677^2 + 3317^2 .

It is not an unprimeable number, because it can be changed into a prime (18168811) 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, 1478 + ... + 6206.

Almost surely, 2^18168818 is an apocalyptic number.

18168818 is a deficient number, since it is larger than the sum of its proper divisors (10949062).

18168818 is a wasteful number, since it uses less digits than its factorization.

18168818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4861.

The product of its digits is 24576, while the sum is 41.

The square root of 18168818 is about 4262.4896480813. The cubic root of 18168818 is about 262.8909030081.

The spelling of 18168818 in words is "eighteen million, one hundred sixty-eight thousand, eight hundred eighteen".