685729 has 16 divisors (see below), whose sum is σ = 838080. Its totient is φ = 552960.

The previous prime is 685723. The next prime is 685733. The reversal of 685729 is 927586.

685729 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 685729 - 2⁵ = 685697 is a prime.

It is a super-2 number, since 2×685729² = 940448522882, which contains 22 as substring.

It is a Duffinian number.

Its product of digits (30240) is a multiple of the sum of its prime divisors (240).

It is not an unprimeable number, because it can be changed into a prime (685723) 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, 3457 + ... + 3649.

It is an arithmetic number, because the mean of its divisors is an integer number (52380).

2⁶⁸⁵⁷²⁹ is an apocalyptic number.

It is an amenable number.

685729 is a deficient number, since it is larger than the sum of its proper divisors (152351).

685729 is a wasteful number, since it uses less digits than its factorization.

685729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240.

The product of its digits is 30240, while the sum is 37.

The square root of 685729 is about 828.0875557572. The cubic root of 685729 is about 88.1828584050.

It can be divided in two parts, 6857 and 29, that added together give a palindrome (6886).

The spelling of 685729 in words is "six hundred eighty-five thousand, seven hundred twenty-nine".