285609 has 4 divisors (see below), whose sum is σ = 380816. Its totient is φ = 190404.

The previous prime is 285599. The next prime is 285611. The reversal of 285609 is 906582.

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 de Polignac number, because none of the positive numbers 2^k-285609 is a prime.

It is a D-number.

It is a Duffinian number.

It is a plaindrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (285629) 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, 47599 + ... + 47604.

It is an arithmetic number, because the mean of its divisors is an integer number (95204).

2²⁸⁵⁶⁰⁹ is an apocalyptic number.

It is an amenable number.

285609 is a deficient number, since it is larger than the sum of its proper divisors (95207).

285609 is an equidigital number, since it uses as much as digits as its factorization.

285609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95206.

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 285609 is about 534.4239889825. The cubic root of 285609 is about 65.8552843889.

The spelling of 285609 in words is "two hundred eighty-five thousand, six hundred nine".