28590228 has 18 divisors (see below), whose sum is σ = 72269834. Its totient is φ = 9530064.

The previous prime is 28590223. The next prime is 28590239. The reversal of 28590228 is 82209582.

It can be written as a sum of positive squares in only one way, i.e., 26193924 + 2396304 = 5118^2 + 1548^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-2 number, since 2×28590228² = 1634802274183968, which contains 22 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 794173 = 28590228 / (2 + 8 + 5 + 9 + 0 + 2 + 2 + 8).

It is a junction number, because it is equal to n+sod(n) for n = 28590192 and 28590201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28590223) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 397051 + ... + 397122.

Almost surely, 2^28590228 is an apocalyptic number.

It is an amenable number.

28590228 is an abundant number, since it is smaller than the sum of its proper divisors (43679606).

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

28590228 is a wasteful number, since it uses less digits than its factorization.

28590228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 794183 (or 794178 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 28590228 is about 5346.9830745945. The cubic root of 28590228 is about 305.7777445430. Note that the first 4 decimals are identical.

The spelling of 28590228 in words is "twenty-eight million, five hundred ninety thousand, two hundred twenty-eight".