21121211020211 has 2 divisors, whose sum is σ = 21121211020212. Its totient is φ = 21121211020210.

The previous prime is 21121211020193. The next prime is 21121211020267. The reversal of 21121211020211 is 11202011212112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21121211020211 - 2¹⁰ = 21121211019187 is a prime.

It is a super-2 number, since 2×21121211020211² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21121211020211.

It is not a weakly prime, because it can be changed into another prime (21121211050211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560605510105 + 10560605510106.

It is an arithmetic number, because the mean of its divisors is an integer number (10560605510106).

Almost surely, 2^{21121211020211} is an apocalyptic number.

21121211020211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21121211020211 is an equidigital number, since it uses as much as digits as its factorization.

21121211020211 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21121211020211 its reverse (11202011212112), we get a palindrome (32323222232323).

The spelling of 21121211020211 in words is "twenty-one trillion, one hundred twenty-one billion, two hundred eleven million, twenty thousand, two hundred eleven".