439991 has 2 divisors, whose sum is σ = 439992. Its totient is φ = 439990.

The previous prime is 439981. The next prime is 440009. The reversal of 439991 is 199934.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 439991 - 2¹⁰ = 438967 is a prime.

It is a Chen prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 439991.

It is not a weakly prime, because it can be changed into another prime (439961) 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, 219995 + 219996.

It is an arithmetic number, because the mean of its divisors is an integer number (219996).

2⁴³⁹⁹⁹¹ is an apocalyptic number.

439991 is a deficient number, since it is larger than the sum of its proper divisors (1).

439991 is an equidigital number, since it uses as much as digits as its factorization.

439991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8748, while the sum is 35.

The square root of 439991 is about 663.3181740311. The cubic root of 439991 is about 76.0585306273.

The spelling of 439991 in words is "four hundred thirty-nine thousand, nine hundred ninety-one".