28728128 has 112 divisors (see below), whose sum is σ = 69470016. Its totient is φ = 11612160.

The previous prime is 28728121. The next prime is 28728151. The reversal of 28728128 is 82182782.

It is a junction number, because it is equal to n+sod(n) for n = 28728091 and 28728100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28728121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 393500 + ... + 393572.

It is an arithmetic number, because the mean of its divisors is an integer number (620268).

Almost surely, 2^28728128 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 28728128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34735008).

28728128 is an abundant number, since it is smaller than the sum of its proper divisors (40741888).

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

28728128 is a wasteful number, since it uses less digits than its factorization.

28728128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152 (or 142 counting only the distinct ones).

The product of its digits is 28672, while the sum is 38.

The square root of 28728128 is about 5359.8626848083. The cubic root of 28728128 is about 306.2685781871.

The spelling of 28728128 in words is "twenty-eight million, seven hundred twenty-eight thousand, one hundred twenty-eight".