285385 has 4 divisors (see below), whose sum is σ = 342468. Its totient is φ = 228304.

The previous prime is 285377. The next prime is 285421. The reversal of 285385 is 583582.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 583582 = 2 ⋅291791.

It can be written as a sum of positive squares in 2 ways, for example, as 84681 + 200704 = 291^2 + 448^2 .

It is a cyclic number.

It is not a de Polignac number, because 285385 - 2³ = 285377 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28534 + ... + 28543.

It is an arithmetic number, because the mean of its divisors is an integer number (85617).

2²⁸⁵³⁸⁵ is an apocalyptic number.

It is an amenable number.

285385 is a deficient number, since it is larger than the sum of its proper divisors (57083).

285385 is an equidigital number, since it uses as much as digits as its factorization.

285385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57082.

The product of its digits is 9600, while the sum is 31.

The square root of 285385 is about 534.2143764445. The cubic root of 285385 is about 65.8380633608.

The spelling of 285385 in words is "two hundred eighty-five thousand, three hundred eighty-five".