111100220121221 has 2 divisors, whose sum is σ = 111100220121222. Its totient is φ = 111100220121220.

The previous prime is 111100220121199. The next prime is 111100220121307. The reversal of 111100220121221 is 122121022001111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 59022189108100 + 52078031013121 = 7682590^2 + 7216511^2 .

It is a cyclic number.

It is not a de Polignac number, because 111100220121221 - 2¹⁴ = 111100220104837 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 111100220121221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111100222121221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55550110060610 + 55550110060611.

It is an arithmetic number, because the mean of its divisors is an integer number (55550110060611).

Almost surely, 2^{111100220121221} is an apocalyptic number.

It is an amenable number.

111100220121221 is a deficient number, since it is larger than the sum of its proper divisors (1).

111100220121221 is an equidigital number, since it uses as much as digits as its factorization.

111100220121221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 111100220121221 its reverse (122121022001111), we get a palindrome (233221242122332).

The spelling of 111100220121221 in words is "one hundred eleven trillion, one hundred billion, two hundred twenty million, one hundred twenty-one thousand, two hundred twenty-one".