728513 has 4 divisors (see below), whose sum is σ = 735828. Its totient is φ = 721200.

The previous prime is 728489. The next prime is 728521. The reversal of 728513 is 315827.

728513 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 659344 + 69169 = 812^2 + 263^2 .

It is a cyclic number.

It is not a de Polignac number, because 728513 - 2¹⁸ = 466369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (728573) 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, 3506 + ... + 3707.

It is an arithmetic number, because the mean of its divisors is an integer number (183957).

2⁷²⁸⁵¹³ is an apocalyptic number.

It is an amenable number.

728513 is a deficient number, since it is larger than the sum of its proper divisors (7315).

728513 is a wasteful number, since it uses less digits than its factorization.

728513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7314.

The product of its digits is 1680, while the sum is 26.

The square root of 728513 is about 853.5297300036. The cubic root of 728513 is about 89.9799543833.

Subtracting from 728513 its reverse (315827), we obtain a triangular number (412686 = T₉₀₈).

The spelling of 728513 in words is "seven hundred twenty-eight thousand, five hundred thirteen".