685583 has 4 divisors (see below), whose sum is σ = 687240. Its totient is φ = 683928.

The previous prime is 685547. The next prime is 685591. The reversal of 685583 is 385586.

It is a Cunningham number, because it is equal to 828²-1.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 685583 - 2⁶ = 685519 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 413 + ... + 1241.

It is an arithmetic number, because the mean of its divisors is an integer number (171810).

2⁶⁸⁵⁵⁸³ is an apocalyptic number.

685583 is a deficient number, since it is larger than the sum of its proper divisors (1657).

685583 is an equidigital number, since it uses as much as digits as its factorization.

685583 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1656.

The product of its digits is 28800, while the sum is 35.

The square root of 685583 is about 827.9993961350. Note that the first 3 decimals coincide. The cubic root of 685583 is about 88.1765995617.

The spelling of 685583 in words is "six hundred eighty-five thousand, five hundred eighty-three".