685306 has 4 divisors (see below), whose sum is σ = 1027962. Its totient is φ = 342652.

The previous prime is 685301. The next prime is 685319. The reversal of 685306 is 603586.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 603586 = 2 ⋅301793.

It can be written as a sum of positive squares in only one way, i.e., 600625 + 84681 = 775^2 + 291^2 .

It is not an unprimeable number, because it can be changed into a prime (685301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 171325 + ... + 171328.

2⁶⁸⁵³⁰⁶ is an apocalyptic number.

685306 is a deficient number, since it is larger than the sum of its proper divisors (342656).

685306 is a wasteful number, since it uses less digits than its factorization.

685306 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 342655.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 685306 is about 827.8321085824. The cubic root of 685306 is about 88.1647224642.

The spelling of 685306 in words is "six hundred eighty-five thousand, three hundred six".