28204228 has 24 divisors (see below), whose sum is σ = 54454680. Its totient is φ = 12698880.

The previous prime is 28204223. The next prime is 28204229. The reversal of 28204228 is 82240282.

It can be written as a sum of positive squares in 4 ways, for example, as 2316484 + 25887744 = 1522^2 + 5088^2 .

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 28204196 and 28204205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28204223) 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 7 ways as a sum of consecutive naturals, for example, 4483 + ... + 8746.

It is an arithmetic number, because the mean of its divisors is an integer number (2268945).

Almost surely, 2^28204228 is an apocalyptic number.

It is an amenable number.

28204228 is a deficient number, since it is larger than the sum of its proper divisors (26250452).

28204228 is a wasteful number, since it uses less digits than its factorization.

28204228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13287 (or 13285 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 28.

The square root of 28204228 is about 5310.7652932511. The cubic root of 28204228 is about 304.3953909913.

The spelling of 28204228 in words is "twenty-eight million, two hundred four thousand, two hundred twenty-eight".