685785 has 16 divisors (see below), whose sum is σ = 1108800. Its totient is φ = 361920.

The previous prime is 685781. The next prime is 685793. The reversal of 685785 is 587586.

It is a happy number.

It is not a de Polignac number, because 685785 - 2² = 685781 is a prime.

It is a super-3 number, since 3×685785³ = 967576250103334875, which contains 333 as substring.

It is an Ulam number.

It is a d-powerful number, because it can be written as 6³ + 8⁵ + 7 + 5² + 8⁶ + 5⁸ .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685781) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1791 + ... + 2139.

It is an arithmetic number, because the mean of its divisors is an integer number (69300).

2⁶⁸⁵⁷⁸⁵ is an apocalyptic number.

It is an amenable number.

685785 is a deficient number, since it is larger than the sum of its proper divisors (423015).

685785 is a wasteful number, since it uses less digits than its factorization.

685785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 488.

The product of its digits is 67200, while the sum is 39.

The square root of 685785 is about 828.1213679166. The cubic root of 685785 is about 88.1852588216.

The spelling of 685785 in words is "six hundred eighty-five thousand, seven hundred eighty-five".