18399668 has 12 divisors (see below), whose sum is σ = 36799392. Its totient is φ = 7885560.

The previous prime is 18399637. The next prime is 18399673. The reversal of 18399668 is 86699381.

18399668 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 328538 + ... + 328593.

It is an arithmetic number, because the mean of its divisors is an integer number (3066616).

Almost surely, 2^18399668 is an apocalyptic number.

It is an amenable number.

18399668 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

18399668 is a wasteful number, since it uses less digits than its factorization.

18399668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 657142 (or 657140 counting only the distinct ones).

The product of its digits is 559872, while the sum is 50.

The square root of 18399668 is about 4289.4834187813. The cubic root of 18399668 is about 263.9996365162. Note that the first 3 decimals are identical.

The spelling of 18399668 in words is "eighteen million, three hundred ninety-nine thousand, six hundred sixty-eight".