3959869 has 2 divisors, whose sum is σ = 3959870. Its totient is φ = 3959868.

The previous prime is 3959849. The next prime is 3959873. The reversal of 3959869 is 9689593.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3080025 + 879844 = 1755^2 + 938^2 .

It is an emirp because it is prime and its reverse (9689593) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3959869 - 2⁹ = 3959357 is a prime.

It is a super-2 number, since 2×3959869² = 31361124994322, which contains 22 as substring.

It is an Ulam number.

3959869 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3959819) 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 as a sum of consecutive naturals, namely, 1979934 + 1979935.

It is an arithmetic number, because the mean of its divisors is an integer number (1979935).

Almost surely, 2^3959869 is an apocalyptic number.

It is an amenable number.

3959869 is a deficient number, since it is larger than the sum of its proper divisors (1).

3959869 is an equidigital number, since it uses as much as digits as its factorization.

3959869 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 524880, while the sum is 49.

The square root of 3959869 is about 1989.9419589526. The cubic root of 3959869 is about 158.2074532874.

The spelling of 3959869 in words is "three million, nine hundred fifty-nine thousand, eight hundred sixty-nine".