320728 has 16 divisors (see below), whose sum is σ = 614880. Its totient is φ = 156768.

The previous prime is 320713. The next prime is 320741. The reversal of 320728 is 827023.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 320699 and 320708.

It is a congruent number.

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, 51 + ... + 802.

It is an arithmetic number, because the mean of its divisors is an integer number (38430).

2³²⁰⁷²⁸ is an apocalyptic number.

It is an amenable number.

320728 is a deficient number, since it is larger than the sum of its proper divisors (294152).

320728 is a wasteful number, since it uses less digits than its factorization.

320728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 906 (or 902 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 320728 is about 566.3285265639. The cubic root of 320728 is about 68.4508678529.

The spelling of 320728 in words is "three hundred twenty thousand, seven hundred twenty-eight".