21000020211211 has 2 divisors, whose sum is σ = 21000020211212. Its totient is φ = 21000020211210.

The previous prime is 21000020211133. The next prime is 21000020211251. The reversal of 21000020211211 is 11211202000012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21000020211211 - 2³¹ = 20997872727563 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21000020211191 and 21000020211200.

It is not a weakly prime, because it can be changed into another prime (21000020211251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500010105605 + 10500010105606.

It is an arithmetic number, because the mean of its divisors is an integer number (10500010105606).

Almost surely, 2^{21000020211211} is an apocalyptic number.

21000020211211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000020211211 is an equidigital number, since it uses as much as digits as its factorization.

21000020211211 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21000020211211 its reverse (11211202000012), we get a palindrome (32211222211223).

The spelling of 21000020211211 in words is "twenty-one trillion, twenty million, two hundred eleven thousand, two hundred eleven".