21012220001211 has 4 divisors (see below), whose sum is σ = 28016293334952. Its totient is φ = 14008146667472.

The previous prime is 21012220001167. The next prime is 21012220001239. The reversal of 21012220001211 is 11210002221012.

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 21012220001211 - 2⁶ = 21012220001147 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21012220001011) 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, 3502036666866 + ... + 3502036666871.

It is an arithmetic number, because the mean of its divisors is an integer number (7004073333738).

Almost surely, 2^{21012220001211} is an apocalyptic number.

21012220001211 is a deficient number, since it is larger than the sum of its proper divisors (7004073333741).

21012220001211 is an equidigital number, since it uses as much as digits as its factorization.

21012220001211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7004073333740.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21012220001211 its reverse (11210002221012), we get a palindrome (32222222222223).

The spelling of 21012220001211 in words is "twenty-one trillion, twelve billion, two hundred twenty million, one thousand, two hundred eleven".