20121221222011 has 16 divisors (see below), whose sum is σ = 24783762588928. Its totient is φ = 15907755434400.

The previous prime is 20121221221991. The next prime is 20121221222017. The reversal of 20121221222011 is 11022212212102.

It is a cyclic number.

It is not a de Polignac number, because 20121221222011 - 2¹⁷ = 20121221090939 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20121221222011.

It is not an unprimeable number, because it can be changed into a prime (20121221222017) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 85518585 + ... + 85753546.

It is an arithmetic number, because the mean of its divisors is an integer number (1548985161808).

Almost surely, 2^{20121221222011} is an apocalyptic number.

20121221222011 is a deficient number, since it is larger than the sum of its proper divisors (4662541366917).

20121221222011 is a wasteful number, since it uses less digits than its factorization.

20121221222011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171273442.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 20121221222011 its reverse (11022212212102), we get a palindrome (31143433434113).

Subtracting from 20121221222011 its reverse (11022212212102), we obtain a palindrome (9099009009909).

The spelling of 20121221222011 in words is "twenty trillion, one hundred twenty-one billion, two hundred twenty-one million, two hundred twenty-two thousand, eleven".