205823 has 2 divisors, whose sum is σ = 205824. Its totient is φ = 205822.

The previous prime is 205817. The next prime is 205837. The reversal of 205823 is 328502.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 205823 - 2⁶ = 205759 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 205795 and 205804.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102911 + 102912.

It is an arithmetic number, because the mean of its divisors is an integer number (102912).

2²⁰⁵⁸²³ is an apocalyptic number.

205823 is a deficient number, since it is larger than the sum of its proper divisors (1).

205823 is an equidigital number, since it uses as much as digits as its factorization.

205823 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 205823 is about 453.6771980164. The cubic root of 205823 is about 59.0424859168.

The spelling of 205823 in words is "two hundred five thousand, eight hundred twenty-three".