1220111211211 has 4 divisors (see below), whose sum is σ = 1230908655672. Its totient is φ = 1209313766752.

The previous prime is 1220111211191. The next prime is 1220111211227. The reversal of 1220111211211 is 1121121110221.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1220111211211 - 2⁹ = 1220111210699 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1220111211251) 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 in 3 ways as a sum of consecutive naturals, for example, 5398722061 + ... + 5398722286.

It is an arithmetic number, because the mean of its divisors is an integer number (307727163918).

Almost surely, 2^{1220111211211} is an apocalyptic number.

1220111211211 is a deficient number, since it is larger than the sum of its proper divisors (10797444461).

1220111211211 is a wasteful number, since it uses less digits than its factorization.

1220111211211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10797444460.

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

Adding to 1220111211211 its reverse (1121121110221), we get a palindrome (2341232321432).

The spelling of 1220111211211 in words is "one trillion, two hundred twenty billion, one hundred eleven million, two hundred eleven thousand, two hundred eleven".