28255 has 4 divisors (see below), whose sum is σ = 33912. Its totient is φ = 22600.

The previous prime is 28229. The next prime is 28277. The reversal of 28255 is 55282.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 28255 - 2⁹ = 27743 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2821 + ... + 2830.

It is an arithmetic number, because the mean of its divisors is an integer number (8478).

2²⁸²⁵⁵ is an apocalyptic number.

28255 is a deficient number, since it is larger than the sum of its proper divisors (5657).

28255 is an equidigital number, since it uses as much as digits as its factorization.

28255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5656.

The product of its digits is 800, while the sum is 22.

The square root of 28255 is about 168.0922365846. The cubic root of 28255 is about 30.4577934526.

It can be divided in two parts, 28 and 255, that multiplied together give a triangular number (7140 = T₁₁₉).

The spelling of 28255 in words is "twenty-eight thousand, two hundred fifty-five".