85609 has 4 divisors (see below), whose sum is σ = 87120. Its totient is φ = 84100.

The previous prime is 85607. The next prime is 85619. The reversal of 85609 is 90658.

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, and also an emirpimes, since its reverse is a distinct semiprime: 90658 = 2 ⋅45329.

It is a cyclic number.

It is not a de Polignac number, because 85609 - 2¹ = 85607 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (85601) 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, 667 + ... + 784.

It is an arithmetic number, because the mean of its divisors is an integer number (21780).

2⁸⁵⁶⁰⁹ is an apocalyptic number.

It is an amenable number.

85609 is a deficient number, since it is larger than the sum of its proper divisors (1511).

85609 is a wasteful number, since it uses less digits than its factorization.

85609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1510.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 85609 is about 292.5901570457. The cubic root of 85609 is about 44.0730535725.

The spelling of 85609 in words is "eighty-five thousand, six hundred nine".