20121222001221 has 48 divisors (see below), whose sum is σ = 31812535360320. Its totient is φ = 12153781935360.

The previous prime is 20121222001217. The next prime is 20121222001259. The reversal of 20121222001221 is 12210022212102.

It is a happy number.

20121222001221 is a `hidden beast` number, since 201 + 21 + 2 + 220 + 0 + 1 + 221 = 666.

It is not a de Polignac number, because 20121222001221 - 2² = 20121222001217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20121222001194 and 20121222001203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20121222001271) 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 47 ways as a sum of consecutive naturals, for example, 207843390 + ... + 207940176.

It is an arithmetic number, because the mean of its divisors is an integer number (662761153340).

Almost surely, 2^{20121222001221} is an apocalyptic number.

It is an amenable number.

20121222001221 is a deficient number, since it is larger than the sum of its proper divisors (11691313359099).

20121222001221 is a wasteful number, since it uses less digits than its factorization.

20121222001221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103826 (or 103823 counting only the distinct ones).

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

Adding to 20121222001221 its reverse (12210022212102), we get a palindrome (32331244213323).

The spelling of 20121222001221 in words is "twenty trillion, one hundred twenty-one billion, two hundred twenty-two million, one thousand, two hundred twenty-one".