211221211111109 has 2 divisors, whose sum is σ = 211221211111110. Its totient is φ = 211221211111108.

The previous prime is 211221211111091. The next prime is 211221211111223. The reversal of 211221211111109 is 901111112122112.

Together with previous prime (211221211111091) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 107399437756900 + 103821773354209 = 10363370^2 + 10189297^2 .

It is a cyclic number.

It is not a de Polignac number, because 211221211111109 - 2⁸ = 211221211110853 is a prime.

It is a super-2 number, since 2×211221211111109² (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 (211221211113109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105610605555554 + 105610605555555.

It is an arithmetic number, because the mean of its divisors is an integer number (105610605555555).

Almost surely, 2^{211221211111109} is an apocalyptic number.

It is an amenable number.

211221211111109 is a deficient number, since it is larger than the sum of its proper divisors (1).

211221211111109 is an equidigital number, since it uses as much as digits as its factorization.

211221211111109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 26.

The spelling of 211221211111109 in words is "two hundred eleven trillion, two hundred twenty-one billion, two hundred eleven million, one hundred eleven thousand, one hundred nine".