685238 has 8 divisors (see below), whose sum is σ = 1035120. Its totient is φ = 340200.

The previous prime is 685231. The next prime is 685247. The reversal of 685238 is 832586.

Added to its reverse (832586) it gives a square (1517824 = 1232²).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×685238² = 939102233288, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685231) by changing a digit.

685238 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 833 + ... + 1436.

It is an arithmetic number, because the mean of its divisors is an integer number (129390).

2⁶⁸⁵²³⁸ is an apocalyptic number.

685238 is a deficient number, since it is larger than the sum of its proper divisors (349882).

685238 is a wasteful number, since it uses less digits than its factorization.

685238 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2422.

The product of its digits is 11520, while the sum is 32.

The square root of 685238 is about 827.7910364337. The cubic root of 685238 is about 88.1618062976.

Adding to 685238 its reverse (832586), we get a square (1517824 = 1232²).

The spelling of 685238 in words is "six hundred eighty-five thousand, two hundred thirty-eight".