28228 has 6 divisors (see below), whose sum is σ = 49406. Its totient is φ = 14112.

The previous prime is 28219. The next prime is 28229. The reversal of 28228 is 82282.

28228 is an esthetic number in base 4, because in such base its adjacent digits differ by 1.

It can be written as a sum of positive squares in only one way, i.e., 28224 + 4 = 168^2 + 2^2 .

It is a junction number, because it is equal to n+sod(n) for n = 28199 and 28208.

It is not an unprimeable number, because it can be changed into a prime (28229) by changing a digit.

28228 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3525 + ... + 3532.

2²⁸²²⁸ is an apocalyptic number.

It is an amenable number.

28228 is a deficient number, since it is larger than the sum of its proper divisors (21178).

28228 is a wasteful number, since it uses less digits than its factorization.

28228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7061 (or 7059 counting only the distinct ones).

The product of its digits is 512, while the sum is 22.

The square root of 28228 is about 168.0119043401. The cubic root of 28228 is about 30.4480887100.

It can be divided in two parts, 28 and 228, that added together give a 8-th power (256 = 2⁸).

The spelling of 28228 in words is "twenty-eight thousand, two hundred twenty-eight".