685869 has 12 divisors (see below), whose sum is σ = 945504. Its totient is φ = 442224.

The previous prime is 685859. The next prime is 685907. The reversal of 685869 is 968586.

It is not a de Polignac number, because 685869 - 2⁸ = 685613 is a prime.

It is a super-2 number, since 2×685869² = 940832570322, which contains 22 as substring.

It is a nialpdrome in base 7.

It is a zygodrome in base 7.

It is a self number, because there is not a number n which added to its sum of digits gives 685869.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685819) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4024 + ... + 4190.

It is an arithmetic number, because the mean of its divisors is an integer number (78792).

2⁶⁸⁵⁸⁶⁹ is an apocalyptic number.

It is an amenable number.

685869 is a deficient number, since it is larger than the sum of its proper divisors (259635).

685869 is a wasteful number, since it uses less digits than its factorization.

685869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 244 (or 207 counting only the distinct ones).

The product of its digits is 103680, while the sum is 42.

The square root of 685869 is about 828.1720835672. The cubic root of 685869 is about 88.1888592013.

The spelling of 685869 in words is "six hundred eighty-five thousand, eight hundred sixty-nine".