221122201212 has 192 divisors, whose sum is σ = 637908203520. Its totient is φ = 65669011200.

The previous prime is 221122201211. The next prime is 221122201241. The reversal of 221122201212 is 212102221122.

It is a happy number.

221122201212 is a `hidden beast` number, since 221 + 12 + 220 + 1 + 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 not an unprimeable number, because it can be changed into a prime (221122201211) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 86952013 + ... + 86954555.

It is an arithmetic number, because the mean of its divisors is an integer number (3322438560).

Almost surely, 2^221122201212 is an apocalyptic number.

221122201212 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 221122201212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (318954101760).

221122201212 is an abundant number, since it is smaller than the sum of its proper divisors (416786002308).

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

221122201212 is a wasteful number, since it uses less digits than its factorization.

221122201212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4001 (or 3993 counting only the distinct ones).

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

Adding to 221122201212 its reverse (212102221122), we get a palindrome (433224422334).

The spelling of 221122201212 in words is "two hundred twenty-one billion, one hundred twenty-two million, two hundred one thousand, two hundred twelve".