221111211122220 has 192 divisors, whose sum is σ = 639585466232832. Its totient is φ = 57016087680000.

The previous prime is 221111211122177. The next prime is 221111211122231. The reversal of 221111211122220 is 22221112111122.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 21911719375 + ... + 21911729465.

It is an arithmetic number, because the mean of its divisors is an integer number (3331174303296).

Almost surely, 2^{221111211122220} is an apocalyptic number.

221111211122220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221111211122220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (319792733116416).

221111211122220 is an abundant number, since it is smaller than the sum of its proper divisors (418474255110612).

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

221111211122220 is a wasteful number, since it uses less digits than its factorization.

221111211122220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18232 (or 18230 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 21.

Adding to 221111211122220 its reverse (22221112111122), we get a palindrome (243332323233342).

The spelling of 221111211122220 in words is "two hundred twenty-one trillion, one hundred eleven billion, two hundred eleven million, one hundred twenty-two thousand, two hundred twenty".