666895689 has 12 divisors (see below), whose sum is σ = 977672176. Its totient is φ = 437960952.

The previous prime is 666895639. The next prime is 666895711. The reversal of 666895689 is 986598666.

It is not a de Polignac number, because 666895689 - 2⁸ = 666895433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666895609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 552379 + ... + 553584.

Almost surely, 2^666895689 is an apocalyptic number.

It is an amenable number.

666895689 is a deficient number, since it is larger than the sum of its proper divisors (310776487).

666895689 is a wasteful number, since it uses less digits than its factorization.

666895689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1106036 (or 1106033 counting only the distinct ones).

The product of its digits is 33592320, while the sum is 63.

The square root of 666895689 is about 25824.3235923034. The cubic root of 666895689 is about 873.6804880016.

The spelling of 666895689 in words is "six hundred sixty-six million, eight hundred ninety-five thousand, six hundred eighty-nine".