16638666 has 16 divisors (see below), whose sum is σ = 36302688. Its totient is φ = 5042000.

The previous prime is 16638653. The next prime is 16638673. The reversal of 16638666 is 66683661.

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, 125985 + ... + 126116.

It is an arithmetic number, because the mean of its divisors is an integer number (2268918).

Almost surely, 2^16638666 is an apocalyptic number.

16638666 is an abundant number, since it is smaller than the sum of its proper divisors (19664022).

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

16638666 is a wasteful number, since it uses less digits than its factorization.

16638666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252117.

The product of its digits is 186624, while the sum is 42.

The square root of 16638666 is about 4079.0520957693. The cubic root of 16638666 is about 255.2933494478.

The spelling of 16638666 in words is "sixteen million, six hundred thirty-eight thousand, six hundred sixty-six".