20021221121211 has 64 divisors (see below), whose sum is σ = 32177351606400. Its totient is φ = 12253834137600.

The previous prime is 20021221121207. The next prime is 20021221121221. The reversal of 20021221121211 is 11212112212002.

20021221121211 is a `hidden beast` number, since 20 + 0 + 212 + 211 + 212 + 11 = 666.

It is not a de Polignac number, because 20021221121211 - 2² = 20021221121207 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20021221121221) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 113371521 + ... + 113547981.

It is an arithmetic number, because the mean of its divisors is an integer number (502771118850).

Almost surely, 2^{20021221121211} is an apocalyptic number.

20021221121211 is a deficient number, since it is larger than the sum of its proper divisors (12156130485189).

20021221121211 is a wasteful number, since it uses less digits than its factorization.

20021221121211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182557 (or 182551 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 20021221121211 its reverse (11212112212002), we get a palindrome (31233333333213).

The spelling of 20021221121211 in words is "twenty trillion, twenty-one billion, two hundred twenty-one million, one hundred twenty-one thousand, two hundred eleven".