28289668 has 12 divisors (see below), whose sum is σ = 54007632. Its totient is φ = 12858920.

The previous prime is 28289647. The next prime is 28289669. The reversal of 28289668 is 86698282.

It is not an unprimeable number, because it can be changed into a prime (28289669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 321430 + ... + 321517.

It is an arithmetic number, because the mean of its divisors is an integer number (4500636).

Almost surely, 2^28289668 is an apocalyptic number.

It is an amenable number.

28289668 is a deficient number, since it is larger than the sum of its proper divisors (25717964).

28289668 is a wasteful number, since it uses less digits than its factorization.

28289668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 642962 (or 642960 counting only the distinct ones).

The product of its digits is 663552, while the sum is 49.

The square root of 28289668 is about 5318.8032488521. The cubic root of 28289668 is about 304.7024528081.

The spelling of 28289668 in words is "twenty-eight million, two hundred eighty-nine thousand, six hundred sixty-eight".