21220221211110 has 256 divisors, whose sum is σ = 58306789094400. Its totient is φ = 5489669376000.

The previous prime is 21220221211097. The next prime is 21220221211117. The reversal of 21220221211110 is 1111212202212.

21220221211110 is a `hidden beast` number, since 2 + 1 + 220 + 221 + 211 + 1 + 10 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220221211117) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 493920030 + ... + 493962990.

It is an arithmetic number, because the mean of its divisors is an integer number (227760894900).

Almost surely, 2^{21220221211110} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21220221211110, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29153394547200).

21220221211110 is an abundant number, since it is smaller than the sum of its proper divisors (37086567883290).

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

21220221211110 is a wasteful number, since it uses less digits than its factorization.

21220221211110 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43444 (or 43438 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21220221211110 its reverse (1111212202212), we get a palindrome (22331433413322).

The spelling of 21220221211110 in words is "twenty-one trillion, two hundred twenty billion, two hundred twenty-one million, two hundred eleven thousand, one hundred ten".