18909666 has 16 divisors (see below), whose sum is σ = 42021600. Its totient is φ = 6303204.

The previous prime is 18909629. The next prime is 18909673. The reversal of 18909666 is 66690981.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 175036 + ... + 175143.

It is an arithmetic number, because the mean of its divisors is an integer number (2626350).

Almost surely, 2^18909666 is an apocalyptic number.

18909666 is an abundant number, since it is smaller than the sum of its proper divisors (23111934).

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

18909666 is a wasteful number, since it uses less digits than its factorization.

18909666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 350190 (or 350184 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 45.

The square root of 18909666 is about 4348.5245773710. The cubic root of 18909666 is about 266.4166027312.

The spelling of 18909666 in words is "eighteen million, nine hundred nine thousand, six hundred sixty-six".