685601 has 4 divisors (see below), whose sum is σ = 783552. Its totient is φ = 587652.

The previous prime is 685591. The next prime is 685609. The reversal of 685601 is 106586.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 685601 - 2⁶ = 685537 is a prime.

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (685609) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48965 + ... + 48978.

It is an arithmetic number, because the mean of its divisors is an integer number (195888).

2⁶⁸⁵⁶⁰¹ is an apocalyptic number.

It is an amenable number.

685601 is a deficient number, since it is larger than the sum of its proper divisors (97951).

685601 is an equidigital number, since it uses as much as digits as its factorization.

685601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97950.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 685601 is about 828.0102656368. The cubic root of 685601 is about 88.1773712479.

The spelling of 685601 in words is "six hundred eighty-five thousand, six hundred one".