205634 has 16 divisors (see below), whose sum is σ = 362880. Its totient is φ = 86160.

The previous prime is 205633. The next prime is 205651. The reversal of 205634 is 436502.

It is not an unprimeable number, because it can be changed into a prime (205633) 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, 74 + ... + 645.

It is an arithmetic number, because the mean of its divisors is an integer number (22680).

2²⁰⁵⁶³⁴ is an apocalyptic number.

205634 is a deficient number, since it is larger than the sum of its proper divisors (157246).

205634 is a wasteful number, since it uses less digits than its factorization.

205634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 745.

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 205634 is about 453.4688522931. The cubic root of 205634 is about 59.0244081716.

The spelling of 205634 in words is "two hundred five thousand, six hundred thirty-four".