28565989 has 8 divisors (see below), whose sum is σ = 29272320. Its totient is φ = 27863856.

The previous prime is 28565951. The next prime is 28566017. The reversal of 28565989 is 98956582.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28565989 - 2¹³ = 28557797 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28565939) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16027 + ... + 17719.

It is an arithmetic number, because the mean of its divisors is an integer number (3659040).

Almost surely, 2^28565989 is an apocalyptic number.

It is an amenable number.

28565989 is a deficient number, since it is larger than the sum of its proper divisors (706331).

28565989 is a wasteful number, since it uses less digits than its factorization.

28565989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2099.

The product of its digits is 1555200, while the sum is 52.

The square root of 28565989 is about 5344.7159887126. The cubic root of 28565989 is about 305.6913065904.

The spelling of 28565989 in words is "twenty-eight million, five hundred sixty-five thousand, nine hundred eighty-nine".