221111111105 has 4 divisors (see below), whose sum is σ = 265333333332. Its totient is φ = 176888888880.

The previous prime is 221111111101. The next prime is 221111111113. The reversal of 221111111105 is 501111111122.

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

It can be written as a sum of positive squares in 2 ways, for example, as 110189474704 + 110921636401 = 331948^2 + 333049^2 .

It is not a de Polignac number, because 221111111105 - 2² = 221111111101 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221111111101) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22111111106 + ... + 22111111115.

It is an arithmetic number, because the mean of its divisors is an integer number (66333333333).

Almost surely, 2^221111111105 is an apocalyptic number.

It is an amenable number.

221111111105 is a deficient number, since it is larger than the sum of its proper divisors (44222222227).

221111111105 is an equidigital number, since it uses as much as digits as its factorization.

221111111105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44222222226.

The product of its (nonzero) digits is 20, while the sum is 17.

Adding to 221111111105 its sum of digits (17), we get a palindrome (221111111122).

Adding to 221111111105 its reverse (501111111122), we get a palindrome (722222222227).

The spelling of 221111111105 in words is "two hundred twenty-one billion, one hundred eleven million, one hundred eleven thousand, one hundred five".