221111111123 has 16 divisors (see below), whose sum is σ = 256120128000. Its totient is φ = 186967230912.

The previous prime is 221111111113. The next prime is 221111111129. The reversal of 221111111123 is 321111111122.

It is not a de Polignac number, because 221111111123 - 2²² = 221106916819 is a prime.

It is a super-2 number, since 2×221111111123² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221111111129) 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, 130733 + ... + 677726.

It is an arithmetic number, because the mean of its divisors is an integer number (16007508000).

Almost surely, 2^221111111123 is an apocalyptic number.

221111111123 is a deficient number, since it is larger than the sum of its proper divisors (35009016877).

221111111123 is an equidigital number, since it uses as much as digits as its factorization.

221111111123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 808994.

The product of its digits is 24, while the sum is 17.

Adding to 221111111123 its reverse (321111111122), we get a palindrome (542222222245).

Subtracting 221111111123 from its reverse (321111111122), we obtain a palindrome (99999999999).

The spelling of 221111111123 in words is "two hundred twenty-one billion, one hundred eleven million, one hundred eleven thousand, one hundred twenty-three".