685823 has 4 divisors (see below), whose sum is σ = 697128. Its totient is φ = 674520.

The previous prime is 685819. The next prime is 685849. The reversal of 685823 is 328586.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 685823 - 2² = 685819 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 685823.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685123) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5561 + ... + 5682.

It is an arithmetic number, because the mean of its divisors is an integer number (174282).

2⁶⁸⁵⁸²³ is an apocalyptic number.

685823 is a deficient number, since it is larger than the sum of its proper divisors (11305).

685823 is a wasteful number, since it uses less digits than its factorization.

685823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11304.

The product of its digits is 11520, while the sum is 32.

The square root of 685823 is about 828.1443110956. The cubic root of 685823 is about 88.1868876012.

The spelling of 685823 in words is "six hundred eighty-five thousand, eight hundred twenty-three".