685240 has 32 divisors (see below), whose sum is σ = 1586880. Its totient is φ = 266112.

The previous prime is 685231. The next prime is 685247. The reversal of 685240 is 42586.

685240 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685247) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1249 + ... + 1711.

It is an arithmetic number, because the mean of its divisors is an integer number (49590).

2⁶⁸⁵²⁴⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 685240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (793440).

685240 is an abundant number, since it is smaller than the sum of its proper divisors (901640).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

685240 is a wasteful number, since it uses less digits than its factorization.

685240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 511 (or 507 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 685240 is about 827.7922444672. The cubic root of 685240 is about 88.1618920700.

The spelling of 685240 in words is "six hundred eighty-five thousand, two hundred forty".