204111411221 has 2 divisors, whose sum is σ = 204111411222. Its totient is φ = 204111411220.

The previous prime is 204111411197. The next prime is 204111411233. The reversal of 204111411221 is 122114111402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 104400718321 + 99710692900 = 323111^2 + 315770^2 .

It is a cyclic number.

It is not a de Polignac number, because 204111411221 - 2⁶ = 204111411157 is a prime.

It is a super-2 number, since 2×204111411221² (a number of 23 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 204111411193 and 204111411202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (204111411121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102055705610 + 102055705611.

It is an arithmetic number, because the mean of its divisors is an integer number (102055705611).

Almost surely, 2^204111411221 is an apocalyptic number.

It is an amenable number.

204111411221 is a deficient number, since it is larger than the sum of its proper divisors (1).

204111411221 is an equidigital number, since it uses as much as digits as its factorization.

204111411221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 204111411221 its reverse (122114111402), we get a palindrome (326225522623).

The spelling of 204111411221 in words is "two hundred four billion, one hundred eleven million, four hundred eleven thousand, two hundred twenty-one".