221111211211 has 16 divisors (see below), whose sum is σ = 260100489600. Its totient is φ = 185786049600.

The previous prime is 221111211187. The next prime is 221111211221. The reversal of 221111211211 is 112112111122.

It is a cyclic number.

It is not a de Polignac number, because 221111211211 - 2⁵ = 221111211179 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221111211221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12893241 + ... + 12910378.

It is an arithmetic number, because the mean of its divisors is an integer number (16256280600).

Almost surely, 2^221111211211 is an apocalyptic number.

221111211211 is a deficient number, since it is larger than the sum of its proper divisors (38989278389).

221111211211 is a wasteful number, since it uses less digits than its factorization.

221111211211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25803690.

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

Adding to 221111211211 its reverse (112112111122), we get a palindrome (333223322333).

The spelling of 221111211211 in words is "two hundred twenty-one billion, one hundred eleven million, two hundred eleven thousand, two hundred eleven".