660668685 has 16 divisors (see below), whose sum is σ = 1057602624. Its totient is φ = 352179072.

The previous prime is 660668651. The next prime is 660668689. The reversal of 660668685 is 586866066.

It is not a de Polignac number, because 660668685 - 2⁷ = 660668557 is a prime.

It is a super-2 number, since 2×660668685² = 872966222679258450, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660668689) 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 15 ways as a sum of consecutive naturals, for example, 23049 + ... + 43041.

It is an arithmetic number, because the mean of its divisors is an integer number (66100164).

Almost surely, 2^660668685 is an apocalyptic number.

It is an amenable number.

660668685 is a deficient number, since it is larger than the sum of its proper divisors (396933939).

660668685 is a wasteful number, since it uses less digits than its factorization.

660668685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22204.

The product of its (nonzero) digits is 2488320, while the sum is 51.

The square root of 660668685 is about 25703.4761267810. The cubic root of 660668685 is about 870.9527084863.

The spelling of 660668685 in words is "six hundred sixty million, six hundred sixty-eight thousand, six hundred eighty-five".