211201121211221 has 2 divisors, whose sum is σ = 211201121211222. Its totient is φ = 211201121211220.

The previous prime is 211201121211209. The next prime is 211201121211229. The reversal of 211201121211221 is 122112121102112.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 181270921488721 + 29930199722500 = 13463689^2 + 5470850^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211201121211221 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 211201121211193 and 211201121211202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211201121211229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105600560605610 + 105600560605611.

It is an arithmetic number, because the mean of its divisors is an integer number (105600560605611).

Almost surely, 2^{211201121211221} is an apocalyptic number.

It is an amenable number.

211201121211221 is a deficient number, since it is larger than the sum of its proper divisors (1).

211201121211221 is an equidigital number, since it uses as much as digits as its factorization.

211201121211221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 20.

Adding to 211201121211221 its reverse (122112121102112), we get a palindrome (333313242313333).

The spelling of 211201121211221 in words is "two hundred eleven trillion, two hundred one billion, one hundred twenty-one million, two hundred eleven thousand, two hundred twenty-one".