810728 has 8 divisors (see below), whose sum is σ = 1520130. Its totient is φ = 405360.

The previous prime is 810697. The next prime is 810737. The reversal of 810728 is 827018.

It can be written as a sum of positive squares in only one way, i.e., 521284 + 289444 = 722^2 + 538^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 810697 and 810706.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 50663 + ... + 50678.

2⁸¹⁰⁷²⁸ is an apocalyptic number.

It is an amenable number.

810728 is a deficient number, since it is larger than the sum of its proper divisors (709402).

810728 is a wasteful number, since it uses less digits than its factorization.

810728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101347 (or 101343 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 26.

The square root of 810728 is about 900.4043536101. The cubic root of 810728 is about 93.2448935479.

Subtracting 810728 from its reverse (827018), we obtain a triangular number (16290 = T₁₈₀).

The spelling of 810728 in words is "eight hundred ten thousand, seven hundred twenty-eight".