111221122011221 has 2 divisors, whose sum is σ = 111221122011222. Its totient is φ = 111221122011220.

The previous prime is 111221122011187. The next prime is 111221122011239. The reversal of 111221122011221 is 122110221122111.

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., 104637330519121 + 6583791492100 = 10229239^2 + 2565890^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-111221122011221 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 111221122011193 and 111221122011202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111221122019221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55610561005610 + 55610561005611.

It is an arithmetic number, because the mean of its divisors is an integer number (55610561005611).

Almost surely, 2^{111221122011221} is an apocalyptic number.

It is an amenable number.

111221122011221 is a deficient number, since it is larger than the sum of its proper divisors (1).

111221122011221 is an equidigital number, since it uses as much as digits as its factorization.

111221122011221 is an odious number, because the sum of its binary digits is odd.

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

Adding to 111221122011221 its reverse (122110221122111), we get a palindrome (233331343133332).

The spelling of 111221122011221 in words is "one hundred eleven trillion, two hundred twenty-one billion, one hundred twenty-two million, eleven thousand, two hundred twenty-one".