28756228 has 12 divisors (see below), whose sum is σ = 50585500. Its totient is φ = 14303616.

The previous prime is 28756223. The next prime is 28756243. The reversal of 28756228 is 82265782.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 2 ways, for example, as 5184 + 28751044 = 72^2 + 5362^2 .

It is not an unprimeable number, because it can be changed into a prime (28756223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 148900 + ... + 149092.

Almost surely, 2^28756228 is an apocalyptic number.

It is an amenable number.

28756228 is a deficient number, since it is larger than the sum of its proper divisors (21829272).

28756228 is an frugal number, since it uses more digits than its factorization.

28756228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 583 (or 195 counting only the distinct ones).

The product of its digits is 107520, while the sum is 40.

The square root of 28756228 is about 5362.4833799276. The cubic root of 28756228 is about 306.3684030299.

The spelling of 28756228 in words is "twenty-eight million, seven hundred fifty-six thousand, two hundred twenty-eight".