21220110220212 has 192 divisors, whose sum is σ = 57358746144000. Its totient is φ = 6775926441984.

The previous prime is 21220110220181. The next prime is 21220110220247. The reversal of 21220110220212 is 21202201102212.

It is a happy number.

21220110220212 is a `hidden beast` number, since 2 + 1 + 220 + 1 + 10 + 220 + 212 = 666.

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

It is a congruent number.

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, 852577464 + ... + 852602352.

It is an arithmetic number, because the mean of its divisors is an integer number (298743469500).

Almost surely, 2^{21220110220212} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21220110220212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28679373072000).

21220110220212 is an abundant number, since it is smaller than the sum of its proper divisors (36138635923788).

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

21220110220212 is a wasteful number, since it uses less digits than its factorization.

21220110220212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27055 (or 27047 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 21220110220212 its reverse (21202201102212), we get a palindrome (42422311322424).

The spelling of 21220110220212 in words is "twenty-one trillion, two hundred twenty billion, one hundred ten million, two hundred twenty thousand, two hundred twelve".