28128 has 24 divisors (see below), whose sum is σ = 74088. Its totient is φ = 9344.

The previous prime is 28123. The next prime is 28151. The reversal of 28128 is 82182.

28128 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (24).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28123) by changing a digit.

28128 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 51 + ... + 242.

It is an arithmetic number, because the mean of its divisors is an integer number (3087).

2²⁸¹²⁸ is an apocalyptic number.

It is an amenable number.

28128 is an abundant number, since it is smaller than the sum of its proper divisors (45960).

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37044).

28128 is a wasteful number, since it uses less digits than its factorization.

28128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 306 (or 298 counting only the distinct ones).

The product of its digits is 256, while the sum is 21.

The square root of 28128 is about 167.7140423459. The cubic root of 28128 is about 30.4120912198.

Subtracting from 28128 its product of digits (256), we obtain a palindrome (27872).

The spelling of 28128 in words is "twenty-eight thousand, one hundred twenty-eight".