205081 has 2 divisors, whose sum is σ = 205082. Its totient is φ = 205080.

The previous prime is 205069. The next prime is 205097. The reversal of 205081 is 180502.

It is a happy number.

It is an a-pointer prime, because the next prime (205097) can be obtained adding 205081 to its sum of digits (16).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 198025 + 7056 = 445^2 + 84^2 .

It is a cyclic number.

It is not a de Polignac number, because 205081 - 2¹⁵ = 172313 is a prime.

It is a super-3 number, since 3×205081³ = 25876023331639323, which contains 333 as substring. Note that it is a super-d number also for d = 2.

205081 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205031) 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 as a sum of consecutive naturals, namely, 102540 + 102541.

It is an arithmetic number, because the mean of its divisors is an integer number (102541).

2²⁰⁵⁰⁸¹ is an apocalyptic number.

It is an amenable number.

205081 is a deficient number, since it is larger than the sum of its proper divisors (1).

205081 is an equidigital number, since it uses as much as digits as its factorization.

205081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 205081 is about 452.8586976089. The cubic root of 205081 is about 58.9714503259.

Adding to 205081 its reverse (180502), we get a palindrome (385583).

The spelling of 205081 in words is "two hundred five thousand, eighty-one".