21222021120012 has 144 divisors (see below), whose sum is σ = 57182670504960. Its totient is φ = 6625261641600.

The previous prime is 21222021120011. The next prime is 21222021120071. The reversal of 21222021120012 is 21002112022212.

It is a happy number.

21222021120012 is a `hidden beast` number, since 21 + 2 + 220 + 211 + 200 + 12 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (21222021120011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3202087 + ... + 7259297.

Almost surely, 2^{21222021120012} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21222021120012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28591335252480).

21222021120012 is an abundant number, since it is smaller than the sum of its proper divisors (35960649384948).

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

21222021120012 is a wasteful number, since it uses less digits than its factorization.

21222021120012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4057404 (or 4057399 counting only the distinct ones).

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

Adding to 21222021120012 its reverse (21002112022212), we get a palindrome (42224133142224).

The spelling of 21222021120012 in words is "twenty-one trillion, two hundred twenty-two billion, twenty-one million, one hundred twenty thousand, twelve".