205512330120121 has 2 divisors, whose sum is σ = 205512330120122. Its totient is φ = 205512330120120.

The previous prime is 205512330120077. The next prime is 205512330120197. The reversal of 205512330120121 is 121021033215502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 110380007303721 + 95132322816400 = 10506189^2 + 9753580^2 .

It is a cyclic number.

It is not a de Polignac number, because 205512330120121 - 2²³ = 205512321731513 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 205512330120121.

It is not a weakly prime, because it can be changed into another prime (205512330120821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102756165060060 + 102756165060061.

It is an arithmetic number, because the mean of its divisors is an integer number (102756165060061).

Almost surely, 2^{205512330120121} is an apocalyptic number.

It is an amenable number.

205512330120121 is a deficient number, since it is larger than the sum of its proper divisors (1).

205512330120121 is an equidigital number, since it uses as much as digits as its factorization.

205512330120121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3600, while the sum is 28.

Adding to 205512330120121 its reverse (121021033215502), we get a palindrome (326533363335623).

The spelling of 205512330120121 in words is "two hundred five trillion, five hundred twelve billion, three hundred thirty million, one hundred twenty thousand, one hundred twenty-one".