28168189 has 16 divisors (see below), whose sum is σ = 33667200. Its totient is φ = 23543520.

The previous prime is 28168187. The next prime is 28168199. The reversal of 28168189 is 98186182.

It is not a de Polignac number, because 28168189 - 2¹ = 28168187 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28168183) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13062 + ... + 15064.

It is an arithmetic number, because the mean of its divisors is an integer number (2104200).

Almost surely, 2^28168189 is an apocalyptic number.

It is an amenable number.

28168189 is a deficient number, since it is larger than the sum of its proper divisors (5499011).

28168189 is an equidigital number, since it uses as much as digits as its factorization.

28168189 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2065 (or 2051 counting only the distinct ones).

The product of its digits is 55296, while the sum is 43.

The square root of 28168189 is about 5307.3711948572. The cubic root of 28168189 is about 304.2656848907.

The spelling of 28168189 in words is "twenty-eight million, one hundred sixty-eight thousand, one hundred eighty-nine".