685215 has 12 divisors (see below), whose sum is σ = 1187784. Its totient is φ = 365424.

The previous prime is 685199. The next prime is 685231. The reversal of 685215 is 512586.

It is an interprime number because it is at equal distance from previous prime (685199) and next prime (685231).

It is not a de Polignac number, because 685215 - 2⁴ = 685199 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7569 + ... + 7658.

It is an arithmetic number, because the mean of its divisors is an integer number (98982).

2⁶⁸⁵²¹⁵ is an apocalyptic number.

685215 is a deficient number, since it is larger than the sum of its proper divisors (502569).

685215 is a wasteful number, since it uses less digits than its factorization.

685215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15238 (or 15235 counting only the distinct ones).

The product of its digits is 2400, while the sum is 27.

The square root of 685215 is about 827.7771439222. Note that the first 3 decimals coincide. The cubic root of 685215 is about 88.1608199035.

It can be divided in two parts, 685 and 215, that added together give a square (900 = 30²).

The spelling of 685215 in words is "six hundred eighty-five thousand, two hundred fifteen".