728319 has 4 divisors (see below), whose sum is σ = 971096. Its totient is φ = 485544.

The previous prime is 728317. The next prime is 728333. The reversal of 728319 is 913827.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 913827 = 3 ⋅304609.

It is not a de Polignac number, because 728319 - 2¹ = 728317 is a prime.

It is a super-2 number, since 2×728319² = 1060897131522, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (728317) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 121384 + ... + 121389.

It is an arithmetic number, because the mean of its divisors is an integer number (242774).

2⁷²⁸³¹⁹ is an apocalyptic number.

728319 is a deficient number, since it is larger than the sum of its proper divisors (242777).

728319 is a wasteful number, since it uses less digits than its factorization.

728319 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242776.

The product of its digits is 3024, while the sum is 30.

The square root of 728319 is about 853.4160767176. The cubic root of 728319 is about 89.9719665776.

It can be divided in two parts, 728 and 319, that multiplied together give a palindrome (232232).

The spelling of 728319 in words is "seven hundred twenty-eight thousand, three hundred nineteen".