28281228 has 24 divisors (see below), whose sum is σ = 66085488. Its totient is φ = 9413376.

The previous prime is 28281181. The next prime is 28281259. The reversal of 28281228 is 82218282.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 10200 + ... + 12672.

It is an arithmetic number, because the mean of its divisors is an integer number (2753562).

Almost surely, 2^28281228 is an apocalyptic number.

It is an amenable number.

28281228 is an abundant number, since it is smaller than the sum of its proper divisors (37804260).

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

28281228 is a wasteful number, since it uses less digits than its factorization.

28281228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3433 (or 3431 counting only the distinct ones).

The product of its digits is 8192, while the sum is 33.

The square root of 28281228 is about 5318.0097781031. The cubic root of 28281228 is about 304.6721479339.

It can be divided in two parts, 282 and 81228, that multiplied together give a triangular number (22906296 = T₆₇₆₈).

The spelling of 28281228 in words is "twenty-eight million, two hundred eighty-one thousand, two hundred twenty-eight".