21120021211 has 2 divisors, whose sum is σ = 21120021212. Its totient is φ = 21120021210.

The previous prime is 21120021187. The next prime is 21120021227. The reversal of 21120021211 is 11212002112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21120021211 - 2³³ = 12530086619 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21120021191 and 21120021200.

It is not a weakly prime, because it can be changed into another prime (21120021271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560010605 + 10560010606.

It is an arithmetic number, because the mean of its divisors is an integer number (10560010606).

Almost surely, 2^21120021211 is an apocalyptic number.

21120021211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21120021211 is an equidigital number, since it uses as much as digits as its factorization.

21120021211 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 21120021211 its reverse (11212002112), we get a palindrome (32332023323).

The spelling of 21120021211 in words is "twenty-one billion, one hundred twenty million, twenty-one thousand, two hundred eleven".