205105 has 16 divisors (see below), whose sum is σ = 276480. Its totient is φ = 145152.

The previous prime is 205103. The next prime is 205111. The reversal of 205105 is 501502.

It is a cyclic number.

It is not a de Polignac number, because 205105 - 2¹ = 205103 is a prime.

It is a super-2 number, since 2×205105² = 84136122050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (205103) 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 15 ways as a sum of consecutive naturals, for example, 1552 + ... + 1678.

It is an arithmetic number, because the mean of its divisors is an integer number (17280).

2²⁰⁵¹⁰⁵ is an apocalyptic number.

It is an amenable number.

205105 is a deficient number, since it is larger than the sum of its proper divisors (71375).

205105 is a wasteful number, since it uses less digits than its factorization.

205105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168.

The product of its (nonzero) digits is 50, while the sum is 13.

The square root of 205105 is about 452.8851951654. The cubic root of 205105 is about 58.9737506521.

Adding to 205105 its reverse (501502), we get a palindrome (706607).

The spelling of 205105 in words is "two hundred five thousand, one hundred five".