3995989 has 2 divisors, whose sum is σ = 3995990. Its totient is φ = 3995988.

The previous prime is 3995977. The next prime is 3996007. The reversal of 3995989 is 9895993.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2007889 + 1988100 = 1417^2 + 1410^2 .

It is an emirp because it is prime and its reverse (9895993) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3995989 - 2¹⁵ = 3963221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3995489) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1997994 + 1997995.

It is an arithmetic number, because the mean of its divisors is an integer number (1997995).

Almost surely, 2^3995989 is an apocalyptic number.

It is an amenable number.

3995989 is a deficient number, since it is larger than the sum of its proper divisors (1).

3995989 is an equidigital number, since it uses as much as digits as its factorization.

3995989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 787320, while the sum is 52.

The square root of 3995989 is about 1998.9969984970. The cubic root of 3995989 is about 158.6870285718.

The spelling of 3995989 in words is "three million, nine hundred ninety-five thousand, nine hundred eighty-nine".