39686 has 4 divisors (see below), whose sum is σ = 59532. Its totient is φ = 19842.

The previous prime is 39679. The next prime is 39703. The reversal of 39686 is 68693.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 68693 = 73 ⋅941.

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 as a sum of consecutive naturals, namely, 9920 + ... + 9923.

It is an arithmetic number, because the mean of its divisors is an integer number (14883).

2³⁹⁶⁸⁶ is an apocalyptic number.

39686 is a deficient number, since it is larger than the sum of its proper divisors (19846).

39686 is a wasteful number, since it uses less digits than its factorization.

39686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19845.

The product of its digits is 7776, while the sum is 32.

The square root of 39686 is about 199.2134533610. The cubic root of 39686 is about 34.1097950035.

The spelling of 39686 in words is "thirty-nine thousand, six hundred eighty-six".