21012120221211 has 12 divisors (see below), whose sum is σ = 34686674650992. Its totient is φ = 12006925840656.

The previous prime is 21012120221171. The next prime is 21012120221293. The reversal of 21012120221211 is 11212202121012.

21012120221211 is a `hidden beast` number, since 21 + 0 + 1 + 212 + 0 + 221 + 211 = 666.

It is not a de Polignac number, because 21012120221211 - 2¹⁷ = 21012120090139 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21012120221011) 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 11 ways as a sum of consecutive naturals, for example, 166762858836 + ... + 166762858961.

It is an arithmetic number, because the mean of its divisors is an integer number (2890556220916).

Almost surely, 2^{21012120221211} is an apocalyptic number.

21012120221211 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21012120221211 is a deficient number, since it is larger than the sum of its proper divisors (13674554429781).

21012120221211 is a wasteful number, since it uses less digits than its factorization.

21012120221211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333525717810 (or 333525717807 counting only the distinct ones).

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

Adding to 21012120221211 its reverse (11212202121012), we get a palindrome (32224322342223).

The spelling of 21012120221211 in words is "twenty-one trillion, twelve billion, one hundred twenty million, two hundred twenty-one thousand, two hundred eleven".