28808 has 16 divisors (see below), whose sum is σ = 58380. Its totient is φ = 13248.

The previous prime is 28807. The next prime is 28813. The reversal of 28808 is 80882.

It can be written as a sum of positive squares in 2 ways, for example, as 24964 + 3844 = 158^2 + 62^2 .

It is a Smith number, since the sum of its digits (26) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 28808.

It is not an unprimeable number, because it can be changed into a prime (28807) 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 3 ways as a sum of consecutive naturals, for example, 35 + ... + 242.

2²⁸⁸⁰⁸ is an apocalyptic number.

It is an amenable number.

28808 is an abundant number, since it is smaller than the sum of its proper divisors (29572).

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29190).

28808 is a wasteful number, since it uses less digits than its factorization.

28808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 296 (or 292 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 26.

The square root of 28808 is about 169.7291960742. The cubic root of 28808 is about 30.6552152161.

Subtracting from 28808 its sum of digits (26), we obtain a palindrome (28782).

The spelling of 28808 in words is "twenty-eight thousand, eight hundred eight".