205505 has 8 divisors (see below), whose sum is σ = 257472. Its totient is φ = 157168.

The previous prime is 205493. The next prime is 205507. The reversal of 205505 is 505502.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 205505 - 2⁶ = 205441 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (205507) 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 7 ways as a sum of consecutive naturals, for example, 779 + ... + 1008.

It is an arithmetic number, because the mean of its divisors is an integer number (32184).

2²⁰⁵⁵⁰⁵ is an apocalyptic number.

It is an amenable number.

205505 is a deficient number, since it is larger than the sum of its proper divisors (51967).

205505 is a wasteful number, since it uses less digits than its factorization.

205505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1815.

The product of its (nonzero) digits is 250, while the sum is 17.

The square root of 205505 is about 453.3265930871. The cubic root of 205505 is about 59.0120630319.

The spelling of 205505 in words is "two hundred five thousand, five hundred five".