685288666 has 16 divisors (see below), whose sum is σ = 1123511040. Its totient is φ = 312085440.

The previous prime is 685288651. The next prime is 685288673. The reversal of 685288666 is 666882586.

It is a happy number.

685288666 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 324036 + ... + 326143.

It is an arithmetic number, because the mean of its divisors is an integer number (70219440).

Almost surely, 2^685288666 is an apocalyptic number.

685288666 is a deficient number, since it is larger than the sum of its proper divisors (438222374).

685288666 is a wasteful number, since it uses less digits than its factorization.

685288666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 650229.

The product of its digits is 6635520, while the sum is 55.

The square root of 685288666 is about 26178.0187562008. The cubic root of 685288666 is about 881.6397911738.

The spelling of 685288666 in words is "six hundred eighty-five million, two hundred eighty-eight thousand, six hundred sixty-six".