212011121222221 has 2 divisors, whose sum is σ = 212011121222222. Its totient is φ = 212011121222220.

The previous prime is 212011121222179. The next prime is 212011121222239. The reversal of 212011121222221 is 122222121110212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 156344764364100 + 55666356858121 = 12503790^2 + 7460989^2 .

It is a cyclic number.

It is not a de Polignac number, because 212011121222221 - 2⁹ = 212011121221709 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 212011121222192 and 212011121222201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212011121622221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106005560611110 + 106005560611111.

It is an arithmetic number, because the mean of its divisors is an integer number (106005560611111).

Almost surely, 2^{212011121222221} is an apocalyptic number.

It is an amenable number.

212011121222221 is a deficient number, since it is larger than the sum of its proper divisors (1).

212011121222221 is an equidigital number, since it uses as much as digits as its factorization.

212011121222221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 256, while the sum is 22.

Adding to 212011121222221 its reverse (122222121110212), we get a palindrome (334233242332433).

The spelling of 212011121222221 in words is "two hundred twelve trillion, eleven billion, one hundred twenty-one million, two hundred twenty-two thousand, two hundred twenty-one".