85209 has 4 divisors (see below), whose sum is σ = 113616. Its totient is φ = 56804.

The previous prime is 85201. The next prime is 85213. The reversal of 85209 is 90258.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 85209 - 2³ = 85201 is a prime.

It is a D-number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 85209.

It is not an unprimeable number, because it can be changed into a prime (85201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14199 + ... + 14204.

It is an arithmetic number, because the mean of its divisors is an integer number (28404).

2⁸⁵²⁰⁹ is an apocalyptic number.

It is an amenable number.

85209 is a deficient number, since it is larger than the sum of its proper divisors (28407).

85209 is a wasteful number, since it uses less digits than its factorization.

85209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28406.

The product of its (nonzero) digits is 720, while the sum is 24.

The square root of 85209 is about 291.9058067254. The cubic root of 85209 is about 44.0043039867.

The spelling of 85209 in words is "eighty-five thousand, two hundred nine".