728165 has 4 divisors (see below), whose sum is σ = 873804. Its totient is φ = 582528.

The previous prime is 728131. The next prime is 728173. The reversal of 728165 is 561827.

728165 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 139876 + 588289 = 374^2 + 767^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-728165 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 728165.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 72812 + ... + 72821.

It is an arithmetic number, because the mean of its divisors is an integer number (218451).

2⁷²⁸¹⁶⁵ is an apocalyptic number.

It is an amenable number.

728165 is a deficient number, since it is larger than the sum of its proper divisors (145639).

728165 is a wasteful number, since it uses less digits than its factorization.

728165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145638.

The product of its digits is 3360, while the sum is 29.

The square root of 728165 is about 853.3258463213. The cubic root of 728165 is about 89.9656247322.

The spelling of 728165 in words is "seven hundred twenty-eight thousand, one hundred sixty-five".