728839 has 2 divisors, whose sum is σ = 728840. Its totient is φ = 728838.

The previous prime is 728837. The next prime is 728843. The reversal of 728839 is 938827.

It is a weak prime.

It is an emirp because it is prime and its reverse (938827) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 728839 - 2¹ = 728837 is a prime.

Together with 728837, it forms a pair of twin primes.

728839 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 728798 and 728807.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (728831) 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, 364419 + 364420.

It is an arithmetic number, because the mean of its divisors is an integer number (364420).

2⁷²⁸⁸³⁹ is an apocalyptic number.

728839 is a deficient number, since it is larger than the sum of its proper divisors (1).

728839 is an equidigital number, since it uses as much as digits as its factorization.

728839 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24192, while the sum is 37.

The square root of 728839 is about 853.7206803165. The cubic root of 728839 is about 89.9933739978.

It can be divided in two parts, 72 and 8839, that added together give a triangular number (8911 = T₁₃₃).

The spelling of 728839 in words is "seven hundred twenty-eight thousand, eight hundred thirty-nine".