28084728 has 64 divisors (see below), whose sum is σ = 80640000. Its totient is φ = 7984512.

The previous prime is 28084723. The next prime is 28084741. The reversal of 28084728 is 82748082.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28084723) 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 15 ways as a sum of consecutive naturals, for example, 58393 + ... + 58871.

It is an arithmetic number, because the mean of its divisors is an integer number (1260000).

Almost surely, 2^28084728 is an apocalyptic number.

28084728 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28084728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40320000).

28084728 is an abundant number, since it is smaller than the sum of its proper divisors (52555272).

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

28084728 is a wasteful number, since it uses less digits than its factorization.

28084728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 844 (or 840 counting only the distinct ones).

The product of its (nonzero) digits is 57344, while the sum is 39.

The square root of 28084728 is about 5299.5026181709. The cubic root of 28084728 is about 303.9648793684.

It can be divided in two parts, 280847 and 28, that added together give a triangular number (280875 = T₇₄₉).

The spelling of 28084728 in words is "twenty-eight million, eighty-four thousand, seven hundred twenty-eight".