1112212121221 has 2 divisors, whose sum is σ = 1112212121222. Its totient is φ = 1112212121220.

The previous prime is 1112212121149. The next prime is 1112212121243. The reversal of 1112212121221 is 1221212122111.

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., 1086262133121 + 25949988100 = 1042239^2 + 161090^2 .

It is a cyclic number.

It is not a de Polignac number, because 1112212121221 - 2¹³ = 1112212113029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1112212121281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 556106060610 + 556106060611.

It is an arithmetic number, because the mean of its divisors is an integer number (556106060611).

Almost surely, 2^{1112212121221} is an apocalyptic number.

It is an amenable number.

1112212121221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1112212121221 is an equidigital number, since it uses as much as digits as its factorization.

1112212121221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 64, while the sum is 19.

Adding to 1112212121221 its reverse (1221212122111), we get a palindrome (2333424243332).

It can be divided in two parts, 11 and 12212121221, that multiplied together give a palindrome (134333333431).

The spelling of 1112212121221 in words is "one trillion, one hundred twelve billion, two hundred twelve million, one hundred twenty-one thousand, two hundred twenty-one".