685775 has 6 divisors (see below), whose sum is σ = 850392. Its totient is φ = 548600.

The previous prime is 685759. The next prime is 685781. The reversal of 685775 is 577586.

It is not a de Polignac number, because 685775 - 2⁴ = 685759 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 13691 + ... + 13740.

It is an arithmetic number, because the mean of its divisors is an integer number (141732).

2⁶⁸⁵⁷⁷⁵ is an apocalyptic number.

685775 is a deficient number, since it is larger than the sum of its proper divisors (164617).

685775 is a wasteful number, since it uses less digits than its factorization.

685775 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27441 (or 27436 counting only the distinct ones).

The product of its digits is 58800, while the sum is 38.

The square root of 685775 is about 828.1153301322. The cubic root of 685775 is about 88.1848301853.

The spelling of 685775 in words is "six hundred eighty-five thousand, seven hundred seventy-five".