22211221212 has 36 divisors (see below), whose sum is σ = 57662468136. Its totient is φ = 7203638880.

The previous prime is 22211221211. The next prime is 22211221229. The reversal of 22211221212 is 21212211222.

It is a happy number.

22211221212 is a `hidden beast` number, since 22 + 211 + 221 + 212 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

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

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22211221211) 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 11 ways as a sum of consecutive naturals, for example, 8336214 + ... + 8338877.

It is an arithmetic number, because the mean of its divisors is an integer number (1601735226).

Almost surely, 2^22211221212 is an apocalyptic number.

It is an amenable number.

22211221212 is an abundant number, since it is smaller than the sum of its proper divisors (35451246924).

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

22211221212 is a wasteful number, since it uses less digits than its factorization.

22211221212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16675138 (or 16675133 counting only the distinct ones).

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

Adding to 22211221212 its reverse (21212211222), we get a palindrome (43423432434).

The spelling of 22211221212 in words is "twenty-two billion, two hundred eleven million, two hundred twenty-one thousand, two hundred twelve".