39986 has 4 divisors (see below), whose sum is σ = 59982. Its totient is φ = 19992.

The previous prime is 39983. The next prime is 39989. The reversal of 39986 is 68993.

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

It is an interprime number because it is at equal distance from previous prime (39983) and next prime (39989).

It can be written as a sum of positive squares in only one way, i.e., 32761 + 7225 = 181^2 + 85^2 .

It is an Ulam number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (39983) by changing a digit.

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, 9995 + ... + 9998.

2³⁹⁹⁸⁶ is an apocalyptic number.

39986 is a deficient number, since it is larger than the sum of its proper divisors (19996).

39986 is a wasteful number, since it uses less digits than its factorization.

39986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19995.

The product of its digits is 11664, while the sum is 35.

The square root of 39986 is about 199.9649969370. The cubic root of 39986 is about 34.1955285241.

It can be divided in two parts, 3998 and 6, that added together give a palindrome (4004).

The spelling of 39986 in words is "thirty-nine thousand, nine hundred eighty-six".