728857 has 8 divisors (see below), whose sum is σ = 773640. Its totient is φ = 685440.

The previous prime is 728851. The next prime is 728867. The reversal of 728857 is 758827.

It can be written as a sum of positive squares in 4 ways, for example, as 41616 + 687241 = 204^2 + 829^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 728857 - 2⁷ = 728729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (728851) 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 7 ways as a sum of consecutive naturals, for example, 883 + ... + 1495.

It is an arithmetic number, because the mean of its divisors is an integer number (96705).

2⁷²⁸⁸⁵⁷ is an apocalyptic number.

It is an amenable number.

728857 is a deficient number, since it is larger than the sum of its proper divisors (44783).

728857 is a wasteful number, since it uses less digits than its factorization.

728857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 683.

The product of its digits is 31360, while the sum is 37.

The square root of 728857 is about 853.7312223411. The cubic root of 728857 is about 89.9941148415.

It can be divided in two parts, 7288 and 57, that multiplied together give a triangular number (415416 = T₉₁₁).

The spelling of 728857 in words is "seven hundred twenty-eight thousand, eight hundred fifty-seven".