3986 has 4 divisors (see below), whose sum is σ = 5982. Its totient is φ = 1992.

The previous prime is 3967. The next prime is 3989. The reversal of 3986 is 6893.

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: 6893 = 61 ⋅113.

It can be written as a sum of positive squares in only one way, i.e., 3025 + 961 = 55^2 + 31^2 .

It is a plaindrome in base 15.

It is a nialpdrome in base 8 and base 16.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 3986.

It is not an unprimeable number, because it can be changed into a prime (3989) by changing a digit.

3986 is an untouchable number, because it is not equal to the sum of proper divisors of any 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, 995 + ... + 998.

2³⁹⁸⁶ is an apocalyptic number.

3986 is a deficient number, since it is larger than the sum of its proper divisors (1996).

3986 is a wasteful number, since it uses less digits than its factorization.

3986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1995.

The product of its digits is 1296, while the sum is 26.

The square root of 3986 is about 63.1347764707. The cubic root of 3986 is about 15.8554691923.

It can be divided in two parts, 398 and 6, that added together give a palindrome (404).

The spelling of 3986 in words is "three thousand, nine hundred eighty-six".