205413213110221 has 2 divisors, whose sum is σ = 205413213110222. Its totient is φ = 205413213110220.

The previous prime is 205413213110173. The next prime is 205413213110257. The reversal of 205413213110221 is 122011312314502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 189693463055625 + 15719750054596 = 13772925^2 + 3964814^2 .

It is a cyclic number.

It is not a de Polignac number, because 205413213110221 - 2²¹ = 205413211013069 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 205413213110221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205413213110291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102706606555110 + 102706606555111.

It is an arithmetic number, because the mean of its divisors is an integer number (102706606555111).

Almost surely, 2^{205413213110221} is an apocalyptic number.

It is an amenable number.

205413213110221 is a deficient number, since it is larger than the sum of its proper divisors (1).

205413213110221 is an equidigital number, since it uses as much as digits as its factorization.

205413213110221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2880, while the sum is 28.

Adding to 205413213110221 its reverse (122011312314502), we get a palindrome (327424525424723).

The spelling of 205413213110221 in words is "two hundred five trillion, four hundred thirteen billion, two hundred thirteen million, one hundred ten thousand, two hundred twenty-one".