85989 has 4 divisors (see below), whose sum is σ = 114656. Its totient is φ = 57324.

The previous prime is 85933. The next prime is 85991. The reversal of 85989 is 98958.

85989 is nontrivially palindromic in base 2.

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 not a de Polignac number, because 85989 - 2⁸ = 85733 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 85989.

It is not an unprimeable number, because it can be changed into a prime (85909) by changing a digit.

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, 14329 + ... + 14334.

It is an arithmetic number, because the mean of its divisors is an integer number (28664).

2⁸⁵⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

85989 is a deficient number, since it is larger than the sum of its proper divisors (28667).

85989 is a wasteful number, since it uses less digits than its factorization.

85989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28666.

The product of its digits is 25920, while the sum is 39.

The square root of 85989 is about 293.2388105282. The cubic root of 85989 is about 44.1381676041.

The spelling of 85989 in words is "eighty-five thousand, nine hundred eighty-nine".