212221222122 has 128 divisors (see below), whose sum is σ = 537069270528. Its totient is φ = 54400896000.

The previous prime is 212221222093. The next prime is 212221222163. The reversal of 212221222122 is 221222122212.

It is a Harshad number since it is a multiple of its sum of digits (21).

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

212221222122 is a modest number, since divided by 21222122 gives 2122 as remainder.

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, 21429372 + ... + 21439272.

It is an arithmetic number, because the mean of its divisors is an integer number (4195853676).

Almost surely, 2^212221222122 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 212221222122, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (268534635264).

212221222122 is an abundant number, since it is smaller than the sum of its proper divisors (324848048406).

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

212221222122 is a wasteful number, since it uses less digits than its factorization.

212221222122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11024.

The product of its digits is 512, while the sum is 21.

Adding to 212221222122 its reverse (221222122212), we get a palindrome (433443344334).

It can be divided in two parts, 21222122212 and 2, that multiplied together give a palindrome (42444244424).

The spelling of 212221222122 in words is "two hundred twelve billion, two hundred twenty-one million, two hundred twenty-two thousand, one hundred twenty-two".