211212122222111 has 2 divisors, whose sum is σ = 211212122222112. Its totient is φ = 211212122222110.

The previous prime is 211212122222089. The next prime is 211212122222131. The reversal of 211212122222111 is 111222221212112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 211212122222111 - 2¹⁸ = 211212121959967 is a prime.

It is a super-2 number, since 2×211212122222111² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211212122222131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105606061111055 + 105606061111056.

It is an arithmetic number, because the mean of its divisors is an integer number (105606061111056).

Almost surely, 2^{211212122222111} is an apocalyptic number.

211212122222111 is a deficient number, since it is larger than the sum of its proper divisors (1).

211212122222111 is an equidigital number, since it uses as much as digits as its factorization.

211212122222111 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 256, while the sum is 23.

Adding to 211212122222111 its reverse (111222221212112), we get a palindrome (322434343434223).

The spelling of 211212122222111 in words is "two hundred eleven trillion, two hundred twelve billion, one hundred twenty-two million, two hundred twenty-two thousand, one hundred eleven".