205573 has 4 divisors (see below), whose sum is σ = 206668. Its totient is φ = 204480.

The previous prime is 205559. The next prime is 205589. The reversal of 205573 is 375502.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 375502 = 2 ⋅187751.

It can be written as a sum of positive squares in 2 ways, for example, as 74529 + 131044 = 273^2 + 362^2 .

It is a cyclic number.

It is not a de Polignac number, because 205573 - 2¹³ = 197381 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 186 + ... + 667.

It is an arithmetic number, because the mean of its divisors is an integer number (51667).

2²⁰⁵⁵⁷³ is an apocalyptic number.

It is an amenable number.

205573 is a deficient number, since it is larger than the sum of its proper divisors (1095).

205573 is an equidigital number, since it uses as much as digits as its factorization.

205573 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1094.

The product of its (nonzero) digits is 1050, while the sum is 22.

The square root of 205573 is about 453.4015879990. The cubic root of 205573 is about 59.0185711911.

The spelling of 205573 in words is "two hundred five thousand, five hundred seventy-three".