21222011121212 has 48 divisors (see below), whose sum is σ = 42651681072000. Its totient is φ = 9137684208960.

The previous prime is 21222011121211. The next prime is 21222011121221. The reversal of 21222011121212 is 21212111022212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222011121211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6458123 + ... + 9173405.

It is an arithmetic number, because the mean of its divisors is an integer number (888576689000).

Almost surely, 2^{21222011121212} is an apocalyptic number.

21222011121212 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21222011121212 is an abundant number, since it is smaller than the sum of its proper divisors (21429669950788).

21222011121212 is a wasteful number, since it uses less digits than its factorization.

21222011121212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2724666 (or 2724664 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 21222011121212 its reverse (21212111022212), we get a palindrome (42434122143424).

The spelling of 21222011121212 in words is "twenty-one trillion, two hundred twenty-two billion, eleven million, one hundred twenty-one thousand, two hundred twelve".