3971989 has 12 divisors (see below), whose sum is σ = 4671264. Its totient is φ = 3367224.

The previous prime is 3971983. The next prime is 3971993. The reversal of 3971989 is 9891793.

It is not a de Polignac number, because 3971989 - 2⁷ = 3971861 is a prime.

It is a super-2 number, since 2×3971989² = 31553393232242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3971983) 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 11 ways as a sum of consecutive naturals, for example, 4654 + ... + 5440.

It is an arithmetic number, because the mean of its divisors is an integer number (389272).

Almost surely, 2^3971989 is an apocalyptic number.

It is an amenable number.

3971989 is a deficient number, since it is larger than the sum of its proper divisors (699275).

3971989 is a wasteful number, since it uses less digits than its factorization.

3971989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 904 (or 897 counting only the distinct ones).

The product of its digits is 122472, while the sum is 46.

The square root of 3971989 is about 1992.9849472588. The cubic root of 3971989 is about 158.3686977947.

The spelling of 3971989 in words is "three million, nine hundred seventy-one thousand, nine hundred eighty-nine".