728128 has 28 divisors (see below), whose sum is σ = 1495552. Its totient is φ = 351360.

The previous prime is 728113. The next prime is 728129. The reversal of 728128 is 821827.

It is a junction number, because it is equal to n+sod(n) for n = 728096 and 728105.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (728129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1801 + ... + 2167.

2⁷²⁸¹²⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 728128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (747776).

728128 is an abundant number, since it is smaller than the sum of its proper divisors (767424).

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

728128 is a wasteful number, since it uses less digits than its factorization.

728128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 410 (or 400 counting only the distinct ones).

The product of its digits is 1792, while the sum is 28.

The square root of 728128 is about 853.3041661682. The cubic root of 728128 is about 89.9641009089.

The spelling of 728128 in words is "seven hundred twenty-eight thousand, one hundred twenty-eight".