685641 has 16 divisors (see below), whose sum is σ = 1013760. Its totient is φ = 408720.

The previous prime is 685637. The next prime is 685649. The reversal of 685641 is 146586.

685641 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 685641 - 2² = 685637 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 685599 and 685608.

It is not an unprimeable number, because it can be changed into a prime (685649) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2476 + ... + 2738.

It is an arithmetic number, because the mean of its divisors is an integer number (63360).

2⁶⁸⁵⁶⁴¹ is an apocalyptic number.

It is an amenable number.

685641 is a deficient number, since it is larger than the sum of its proper divisors (328119).

685641 is a wasteful number, since it uses less digits than its factorization.

685641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 356.

The product of its digits is 5760, while the sum is 30.

The square root of 685641 is about 828.0344195745. The cubic root of 685641 is about 88.1790860579.

It can be divided in two parts, 685 and 641, that added together give a triangular number (1326 = T₅₁).

The spelling of 685641 in words is "six hundred eighty-five thousand, six hundred forty-one".