3665989 has 2 divisors, whose sum is σ = 3665990. Its totient is φ = 3665988.

The previous prime is 3665941. The next prime is 3666001. The reversal of 3665989 is 9895663.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2377764 + 1288225 = 1542^2 + 1135^2 .

It is an emirp because it is prime and its reverse (9895663) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3665989 - 2⁹ = 3665477 is a prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3665939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1832994 + 1832995.

It is an arithmetic number, because the mean of its divisors is an integer number (1832995).

Almost surely, 2^3665989 is an apocalyptic number.

It is an amenable number.

3665989 is a deficient number, since it is larger than the sum of its proper divisors (1).

3665989 is an equidigital number, since it uses as much as digits as its factorization.

3665989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 349920, while the sum is 46.

The square root of 3665989 is about 1914.6772573988. The cubic root of 3665989 is about 154.1926665994.

The spelling of 3665989 in words is "three million, six hundred sixty-five thousand, nine hundred eighty-nine".