28689 has 8 divisors (see below), whose sum is σ = 39072. Its totient is φ = 18720.

The previous prime is 28687. The next prime is 28697. The reversal of 28689 is 98682.

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

It is not a de Polignac number, because 28689 - 2¹ = 28687 is a prime.

28689 is a lucky number.

It is a nialpdrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (28687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 154 + ... + 284.

It is an arithmetic number, because the mean of its divisors is an integer number (4884).

2²⁸⁶⁸⁹ is an apocalyptic number.

It is an amenable number.

28689 is a deficient number, since it is larger than the sum of its proper divisors (10383).

28689 is a wasteful number, since it uses less digits than its factorization.

28689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 207.

The product of its digits is 6912, while the sum is 33.

The square root of 28689 is about 169.3782748761. The cubic root of 28689 is about 30.6129468048.

It can be divided in two parts, 28 and 689, that added together give a palindrome (717).

The spelling of 28689 in words is "twenty-eight thousand, six hundred eighty-nine".