28522728 has 96 divisors (see below), whose sum is σ = 85962240. Its totient is φ = 8484480.

The previous prime is 28522727. The next prime is 28522733. The reversal of 28522728 is 82722582.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 28522692 and 28522701.

It is not an unprimeable number, because it can be changed into a prime (28522727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 28525 + ... + 29507.

It is an arithmetic number, because the mean of its divisors is an integer number (895440).

Almost surely, 2^28522728 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 28522728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42981120).

28522728 is an abundant number, since it is smaller than the sum of its proper divisors (57439512).

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

28522728 is a wasteful number, since it uses less digits than its factorization.

28522728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1039 (or 1032 counting only the distinct ones).

The product of its digits is 35840, while the sum is 36.

The square root of 28522728 is about 5340.6673740273. The cubic root of 28522728 is about 305.5369132771.

The spelling of 28522728 in words is "twenty-eight million, five hundred twenty-two thousand, seven hundred twenty-eight".