6659666 has 16 divisors (see below), whose sum is σ = 10921344. Its totient is φ = 3027024.

The previous prime is 6659663. The next prime is 6659677. The reversal of 6659666 is 6669566.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (6659663) 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, 170 + ... + 3653.

It is an arithmetic number, because the mean of its divisors is an integer number (682584).

Almost surely, 2^6659666 is an apocalyptic number.

6659666 is a deficient number, since it is larger than the sum of its proper divisors (4261678).

6659666 is a wasteful number, since it uses less digits than its factorization.

6659666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3905.

The product of its digits is 349920, while the sum is 44.

The square root of 6659666 is about 2580.6328681159. The cubic root of 6659666 is about 188.1413039074.

The spelling of 6659666 in words is "six million, six hundred fifty-nine thousand, six hundred sixty-six".