666648866 has 32 divisors (see below), whose sum is σ = 1105429248. Its totient is φ = 299577600.

The previous prime is 666648793. The next prime is 666648881. The reversal of 666648866 is 668846666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 447575 + ... + 449061.

It is an arithmetic number, because the mean of its divisors is an integer number (34544664).

Almost surely, 2^666648866 is an apocalyptic number.

666648866 is a deficient number, since it is larger than the sum of its proper divisors (438780382).

666648866 is a wasteful number, since it uses less digits than its factorization.

666648866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1946.

The product of its digits is 11943936, while the sum is 56.

The square root of 666648866 is about 25819.5442639873. The cubic root of 666648866 is about 873.5726895098.

The spelling of 666648866 in words is "six hundred sixty-six million, six hundred forty-eight thousand, eight hundred sixty-six".