39685 has 4 divisors (see below), whose sum is σ = 47628. Its totient is φ = 31744.

The previous prime is 39679. The next prime is 39703. The reversal of 39685 is 58693.

39685 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 30276 + 9409 = 174^2 + 97^2 .

It is a cyclic number.

It is not a de Polignac number, because 39685 - 2¹⁵ = 6917 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.

39685 is strictly pandigital in base 6.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3964 + ... + 3973.

It is an arithmetic number, because the mean of its divisors is an integer number (11907).

2³⁹⁶⁸⁵ is an apocalyptic number.

It is an amenable number.

39685 is a deficient number, since it is larger than the sum of its proper divisors (7943).

39685 is an equidigital number, since it uses as much as digits as its factorization.

39685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7942.

The product of its digits is 6480, while the sum is 31.

The square root of 39685 is about 199.2109434745. The cubic root of 39685 is about 34.1095085038.

The spelling of 39685 in words is "thirty-nine thousand, six hundred eighty-five".