685507 has 4 divisors (see below), whose sum is σ = 687456. Its totient is φ = 683560.

The previous prime is 685493. The next prime is 685511. The reversal of 685507 is 705586.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 685507 - 2¹⁵ = 652739 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (685537) by changing a digit.

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, 283 + ... + 1204.

It is an arithmetic number, because the mean of its divisors is an integer number (171864).

2⁶⁸⁵⁵⁰⁷ is an apocalyptic number.

685507 is a deficient number, since it is larger than the sum of its proper divisors (1949).

685507 is a wasteful number, since it uses less digits than its factorization.

685507 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1948.

The product of its (nonzero) digits is 8400, while the sum is 31.

The square root of 685507 is about 827.9535011098. The cubic root of 685507 is about 88.1733411820.

The spelling of 685507 in words is "six hundred eighty-five thousand, five hundred seven".