22221220212 has 30 divisors (see below), whose sum is σ = 58090659858. Its totient is φ = 7407073296.

The previous prime is 22221220079. The next prime is 22221220213. The reversal of 22221220212 is 21202212222.

22221220212 is a `hidden beast` number, since 222 + 212 + 20 + 212 = 666.

It can be written as a sum of positive squares in only one way, i.e., 14574767076 + 7646453136 = 120726^2 + 87444^2 .

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 (22221220213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 34291683 + ... + 34292330.

Almost surely, 2^22221220212 is an apocalyptic number.

It is an amenable number.

22221220212 is an abundant number, since it is smaller than the sum of its proper divisors (35869439646).

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

22221220212 is a wasteful number, since it uses less digits than its factorization.

22221220212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68584029 (or 68584018 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

Adding to 22221220212 its reverse (21202212222), we get a palindrome (43423432434).

The spelling of 22221220212 in words is "twenty-two billion, two hundred twenty-one million, two hundred twenty thousand, two hundred twelve".