728291 has 4 divisors (see below), whose sum is σ = 745272. Its totient is φ = 711312.

The previous prime is 728281. The next prime is 728293. The reversal of 728291 is 192827.

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: 192827 = 151 ⋅1277.

It is a cyclic number.

It is not a de Polignac number, because 728291 - 2¹⁰ = 727267 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (728293) 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 in 3 ways as a sum of consecutive naturals, for example, 8426 + ... + 8511.

It is an arithmetic number, because the mean of its divisors is an integer number (186318).

2⁷²⁸²⁹¹ is an apocalyptic number.

728291 is a deficient number, since it is larger than the sum of its proper divisors (16981).

728291 is a wasteful number, since it uses less digits than its factorization.

728291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16980.

The product of its digits is 2016, while the sum is 29.

The square root of 728291 is about 853.3996719006. The cubic root of 728291 is about 89.9708135813.

The spelling of 728291 in words is "seven hundred twenty-eight thousand, two hundred ninety-one".