685508 has 18 divisors (see below), whose sum is σ = 1276506. Its totient is φ = 322048.

The previous prime is 685493. The next prime is 685511. The reversal of 685508 is 805586.

685508 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 315844 + 369664 = 562^2 + 608^2 .

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 685508.

It is an unprimeable number.

685508 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 860 + ... + 1452.

It is an arithmetic number, because the mean of its divisors is an integer number (70917).

2⁶⁸⁵⁵⁰⁸ is an apocalyptic number.

685508 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

685508 is a deficient number, since it is larger than the sum of its proper divisors (590998).

685508 is a wasteful number, since it uses less digits than its factorization.

685508 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 631 (or 612 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 32.

The square root of 685508 is about 827.9541050082. The cubic root of 685508 is about 88.1733840570.

It can be divided in two parts, 68 and 5508, that multiplied together give a square (374544 = 612²).

The spelling of 685508 in words is "six hundred eighty-five thousand, five hundred eight".