864439 has 2 divisors, whose sum is σ = 864440. Its totient is φ = 864438.

The previous prime is 864427. The next prime is 864449. The reversal of 864439 is 934468.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 864439 - 2⁵ = 864407 is a prime.

864439 is a lucky number.

It is equal to p₆₈₆₇₇ and since 864439 and 68677 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (864419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 432219 + 432220.

It is an arithmetic number, because the mean of its divisors is an integer number (432220).

2⁸⁶⁴⁴³⁹ is an apocalyptic number.

864439 is a deficient number, since it is larger than the sum of its proper divisors (1).

864439 is an equidigital number, since it uses as much as digits as its factorization.

864439 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20736, while the sum is 34.

The square root of 864439 is about 929.7521175023. The cubic root of 864439 is about 95.2601916150.

The spelling of 864439 in words is "eight hundred sixty-four thousand, four hundred thirty-nine".