666444666 has 16 divisors (see below), whose sum is σ = 1368913824. Its totient is φ = 216144144.

The previous prime is 666444607. The next prime is 666444673.

666444666 is nontrivially palindromic in base 10.

It is a Curzon number.

It is a zygodrome in base 10.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1500780 + ... + 1501223.

It is an arithmetic number, because the mean of its divisors is an integer number (85557114).

Almost surely, 2^666444666 is an apocalyptic number.

666444666 is an abundant number, since it is smaller than the sum of its proper divisors (702469158).

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

666444666 is a wasteful number, since it uses less digits than its factorization.

666444666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3002045.

The product of its digits is 2985984, while the sum is 48.

The square root of 666444666 is about 25815.5895923374. The cubic root of 666444666 is about 873.4834862481.

The spelling of 666444666 in words is "six hundred sixty-six million, four hundred forty-four thousand, six hundred sixty-six".