666841768 has 8 divisors (see below), whose sum is σ = 1250328330. Its totient is φ = 333420880.

The previous prime is 666841759. The next prime is 666841771. The reversal of 666841768 is 867148666.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 476898244 + 189943524 = 21838^2 + 13782^2 .

It is a tau number, because it is divible by the number of its divisors (8).

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 as a sum of consecutive naturals, namely, 41677603 + ... + 41677618.

Almost surely, 2^666841768 is an apocalyptic number.

It is an amenable number.

666841768 is a deficient number, since it is larger than the sum of its proper divisors (583486562).

666841768 is a wasteful number, since it uses less digits than its factorization.

666841768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83355227 (or 83355223 counting only the distinct ones).

The product of its digits is 2322432, while the sum is 52.

The square root of 666841768 is about 25823.2795748332. The cubic root of 666841768 is about 873.6569405933.

The spelling of 666841768 in words is "six hundred sixty-six million, eight hundred forty-one thousand, seven hundred sixty-eight".