1211221111117 has 2 divisors, whose sum is σ = 1211221111118. Its totient is φ = 1211221111116.

The previous prime is 1211221111109. The next prime is 1211221111151. The reversal of 1211221111117 is 7111111221121.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1201678556521 + 9542554596 = 1096211^2 + 97686^2 .

It is a cyclic number.

It is not a de Polignac number, because 1211221111117 - 2³ = 1211221111109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1211221111187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605610555558 + 605610555559.

It is an arithmetic number, because the mean of its divisors is an integer number (605610555559).

Almost surely, 2^{1211221111117} is an apocalyptic number.

It is an amenable number.

1211221111117 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211221111117 is an equidigital number, since it uses as much as digits as its factorization.

1211221111117 is an evil number, because the sum of its binary digits is even.

The product of its digits is 56, while the sum is 22.

Adding to 1211221111117 its reverse (7111111221121), we get a palindrome (8322332332238).

The spelling of 1211221111117 in words is "one trillion, two hundred eleven billion, two hundred twenty-one million, one hundred eleven thousand, one hundred seventeen".