28085 has 8 divisors (see below), whose sum is σ = 34776. Its totient is φ = 21760.

The previous prime is 28081. The next prime is 28087. The reversal of 28085 is 58082.

28085 = 118² + 119².

It can be written as a sum of positive squares in 4 ways, for example, as 196 + 27889 = 14^2 + 167^2 .

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

It is not a de Polignac number, because 28085 - 2² = 28081 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a nialpdrome in base 8.

It is a self number, because there is not a number n which added to its sum of digits gives 28085.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28081) 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, 137 + ... + 273.

It is an arithmetic number, because the mean of its divisors is an integer number (4347).

2²⁸⁰⁸⁵ is an apocalyptic number.

28085 is the 137-th pentagonal number.

28085 is the 119-th centered square number.

It is an amenable number.

28085 is a deficient number, since it is larger than the sum of its proper divisors (6691).

28085 is a wasteful number, since it uses less digits than its factorization.

28085 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 183.

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 28085 is about 167.5857989210. The cubic root of 28085 is about 30.3965860663.

The spelling of 28085 in words is "twenty-eight thousand, eighty-five".