28666228 has 12 divisors (see below), whose sum is σ = 50210020. Its totient is φ = 14320512.

The previous prime is 28666219. The next prime is 28666229. The reversal of 28666228 is 82266682.

It can be written as a sum of positive squares in 2 ways, for example, as 13704804 + 14961424 = 3702^2 + 3868^2 .

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28666229) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3550 + ... + 8362.

Almost surely, 2^28666228 is an apocalyptic number.

It is an amenable number.

28666228 is a deficient number, since it is larger than the sum of its proper divisors (21543792).

28666228 is a wasteful number, since it uses less digits than its factorization.

28666228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6306 (or 6304 counting only the distinct ones).

The product of its digits is 110592, while the sum is 40.

The square root of 28666228 is about 5354.0851692890. The cubic root of 28666228 is about 306.0484494746.

The spelling of 28666228 in words is "twenty-eight million, six hundred sixty-six thousand, two hundred twenty-eight".