21222111122212 has 384 divisors, whose sum is σ = 51385201459200. Its totient is φ = 7402755594240.

The previous prime is 21222111122207. The next prime is 21222111122213.

21222111122212 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (21222111122213) 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, 24198529918 + ... + 24198530794.

It is an arithmetic number, because the mean of its divisors is an integer number (133815628800).

Almost surely, 2^{21222111122212} is an apocalyptic number.

21222111122212 is a gapful number since it is divisible by the number (22) 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 21222111122212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25692600729600).

21222111122212 is an abundant number, since it is smaller than the sum of its proper divisors (30163090336988).

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

21222111122212 is a wasteful number, since it uses less digits than its factorization.

21222111122212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1971 (or 1969 counting only the distinct ones).

The product of its digits is 256, while the sum is 22.

Multiplying 21222111122212 by its sum of digits (22), we get a palindrome (466886444688664).

It can be divided in two parts, 2122211 and 1122212, that added together give a palindrome (3244423).

The spelling of 21222111122212 in words is "twenty-one trillion, two hundred twenty-two billion, one hundred eleven million, one hundred twenty-two thousand, two hundred twelve".