20121221112211 has 4 divisors (see below), whose sum is σ = 20770292761024. Its totient is φ = 19472149463400.

The previous prime is 20121221112203. The next prime is 20121221112217. The reversal of 20121221112211 is 11221112212102.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20121221112211 - 2³ = 20121221112203 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20121221112217) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 324535824360 + ... + 324535824421.

It is an arithmetic number, because the mean of its divisors is an integer number (5192573190256).

Almost surely, 2^{20121221112211} is an apocalyptic number.

20121221112211 is a deficient number, since it is larger than the sum of its proper divisors (649071648813).

20121221112211 is an equidigital number, since it uses as much as digits as its factorization.

20121221112211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 649071648812.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 20121221112211 its reverse (11221112212102), we get a palindrome (31342333324313).

The spelling of 20121221112211 in words is "twenty trillion, one hundred twenty-one billion, two hundred twenty-one million, one hundred twelve thousand, two hundred eleven".