728240 has 20 divisors (see below), whose sum is σ = 1693344. Its totient is φ = 291264.

The previous prime is 728209. The next prime is 728261. The reversal of 728240 is 42827.

It is a tau number, because it is divible by the number of its divisors (20).

It is an Ulam 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, 4472 + ... + 4631.

2⁷²⁸²⁴⁰ is an apocalyptic number.

It is an amenable number.

728240 is an abundant number, since it is smaller than the sum of its proper divisors (965104).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

728240 is a wasteful number, since it uses less digits than its factorization.

728240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9116 (or 9110 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 23.

The square root of 728240 is about 853.3697908879. The cubic root of 728240 is about 89.9687134050.

The spelling of 728240 in words is "seven hundred twenty-eight thousand, two hundred forty".