4000439 has 2 divisors, whose sum is σ = 4000440. Its totient is φ = 4000438.

The previous prime is 4000379. The next prime is 4000489. The reversal of 4000439 is 9340004.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-4000439 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 4000439.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4000489) 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, 2000219 + 2000220.

It is an arithmetic number, because the mean of its divisors is an integer number (2000220).

Almost surely, 2^4000439 is an apocalyptic number.

4000439 is a deficient number, since it is larger than the sum of its proper divisors (1).

4000439 is an equidigital number, since it uses as much as digits as its factorization.

4000439 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 4000439 is about 2000.1097469889. The cubic root of 4000439 is about 158.7459122266.

The spelling of 4000439 in words is "four million, four hundred thirty-nine", and thus it is an aban number.