221111111220 has 48 divisors (see below), whose sum is σ = 619240872768. Its totient is φ = 58950604800.

The previous prime is 221111111197. The next prime is 221111111237. The reversal of 221111111220 is 22111111122.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 221111111220.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 95734 + ... + 671853.

It is an arithmetic number, because the mean of its divisors is an integer number (12900851516).

Almost surely, 2^221111111220 is an apocalyptic number.

221111111220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221111111220 is an abundant number, since it is smaller than the sum of its proper divisors (398129761548).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221111111220 is a wasteful number, since it uses less digits than its factorization.

221111111220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 772400 (or 772398 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 221111111220 its reverse (22111111122), we get a palindrome (243222222342).

The spelling of 221111111220 in words is "two hundred twenty-one billion, one hundred eleven million, one hundred eleven thousand, two hundred twenty".