21201021211 has 2 divisors, whose sum is σ = 21201021212. Its totient is φ = 21201021210.

The previous prime is 21201021173. The next prime is 21201021223. The reversal of 21201021211 is 11212010212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21201021211 - 2¹³ = 21201013019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21201021191 and 21201021200.

It is not a weakly prime, because it can be changed into another prime (21201051211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600510605 + 10600510606.

It is an arithmetic number, because the mean of its divisors is an integer number (10600510606).

Almost surely, 2^21201021211 is an apocalyptic number.

21201021211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201021211 is an equidigital number, since it uses as much as digits as its factorization.

21201021211 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 21201021211 its reverse (11212010212), we get a palindrome (32413031423).

It can be divided in two parts, 212010212 and 11, that multiplied together give a palindrome (2332112332).

The spelling of 21201021211 in words is "twenty-one billion, two hundred one million, twenty-one thousand, two hundred eleven".