1220121111211 has 2 divisors, whose sum is σ = 1220121111212. Its totient is φ = 1220121111210.

The previous prime is 1220121111199. The next prime is 1220121111217. The reversal of 1220121111211 is 1121111210221.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1220121111211 - 2⁵ = 1220121111179 is a prime.

It is not a weakly prime, because it can be changed into another prime (1220121111217) 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, 610060555605 + 610060555606.

It is an arithmetic number, because the mean of its divisors is an integer number (610060555606).

Almost surely, 2^{1220121111211} is an apocalyptic number.

1220121111211 is a deficient number, since it is larger than the sum of its proper divisors (1).

1220121111211 is an equidigital number, since it uses as much as digits as its factorization.

1220121111211 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 16.

Adding to 1220121111211 its reverse (1121111210221), we get a palindrome (2341232321432).

The spelling of 1220121111211 in words is "one trillion, two hundred twenty billion, one hundred twenty-one million, one hundred eleven thousand, two hundred eleven".