285643 has 2 divisors, whose sum is σ = 285644. Its totient is φ = 285642.

The previous prime is 285641. The next prime is 285661. The reversal of 285643 is 346582.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 285643 - 2¹ = 285641 is a prime.

Together with 285641, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (285641) 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 as a sum of consecutive naturals, namely, 142821 + 142822.

It is an arithmetic number, because the mean of its divisors is an integer number (142822).

2²⁸⁵⁶⁴³ is an apocalyptic number.

285643 is a deficient number, since it is larger than the sum of its proper divisors (1).

285643 is an equidigital number, since it uses as much as digits as its factorization.

285643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5760, while the sum is 28.

The square root of 285643 is about 534.4557979852. The cubic root of 285643 is about 65.8578975078.

It can be divided in two parts, 28 and 5643, that added together give a triangular number (5671 = T₁₀₆).

The spelling of 285643 in words is "two hundred eighty-five thousand, six hundred forty-three".