21012002122211 has 4 divisors (see below), whose sum is σ = 21012957365472. Its totient is φ = 21011046878952.

The previous prime is 21012002122187. The next prime is 21012002122217. The reversal of 21012002122211 is 11222120021012.

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 21012002122211 - 2⁶ = 21012002122147 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21012002122211.

It is not an unprimeable number, because it can be changed into a prime (21012002122217) 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 3 ways as a sum of consecutive naturals, for example, 477588635 + ... + 477632628.

It is an arithmetic number, because the mean of its divisors is an integer number (5253239341368).

Almost surely, 2^{21012002122211} is an apocalyptic number.

21012002122211 is a deficient number, since it is larger than the sum of its proper divisors (955243261).

21012002122211 is an equidigital number, since it uses as much as digits as its factorization.

21012002122211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 955243260.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21012002122211 its reverse (11222120021012), we get a palindrome (32234122143223).

The spelling of 21012002122211 in words is "twenty-one trillion, twelve billion, two million, one hundred twenty-two thousand, two hundred eleven".