728439 has 4 divisors (see below), whose sum is σ = 971256. Its totient is φ = 485624.

The previous prime is 728437. The next prime is 728471. The reversal of 728439 is 934827.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 934827 = 3 ⋅311609.

It is a cyclic number.

It is not a de Polignac number, because 728439 - 2¹ = 728437 is a prime.

It is a D-number.

728439 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (728437) 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 in 3 ways as a sum of consecutive naturals, for example, 121404 + ... + 121409.

It is an arithmetic number, because the mean of its divisors is an integer number (242814).

2⁷²⁸⁴³⁹ is an apocalyptic number.

728439 is a deficient number, since it is larger than the sum of its proper divisors (242817).

728439 is a wasteful number, since it uses less digits than its factorization.

728439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242816.

The product of its digits is 12096, while the sum is 33.

The square root of 728439 is about 853.4863795047. The cubic root of 728439 is about 89.9769076557.

The spelling of 728439 in words is "seven hundred twenty-eight thousand, four hundred thirty-nine".