3911987 has 4 divisors (see below), whose sum is σ = 3918096. Its totient is φ = 3905880.

The previous prime is 3911977. The next prime is 3912017. The reversal of 3911987 is 7891193.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7891193 = 67 ⋅117779.

It is a cyclic number.

It is not a de Polignac number, because 3911987 - 2⁶ = 3911923 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 3911987.

It is not an unprimeable number, because it can be changed into a prime (3911927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1964 + ... + 3417.

It is an arithmetic number, because the mean of its divisors is an integer number (979524).

Almost surely, 2^3911987 is an apocalyptic number.

3911987 is a deficient number, since it is larger than the sum of its proper divisors (6109).

3911987 is an equidigital number, since it uses as much as digits as its factorization.

3911987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6108.

The product of its digits is 13608, while the sum is 38.

The square root of 3911987 is about 1977.8743640585. The cubic root of 3911987 is about 157.5671939712.

The spelling of 3911987 in words is "three million, nine hundred eleven thousand, nine hundred eighty-seven".