21001210211 has 2 divisors, whose sum is σ = 21001210212. Its totient is φ = 21001210210.

The previous prime is 21001210187. The next prime is 21001210229. The reversal of 21001210211 is 11201210012.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21001210211 is a prime.

It is a super-2 number, since 2×21001210211² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21001210192 and 21001210201.

It is not a weakly prime, because it can be changed into another prime (21001210261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500605105 + 10500605106.

It is an arithmetic number, because the mean of its divisors is an integer number (10500605106).

Almost surely, 2^21001210211 is an apocalyptic number.

21001210211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21001210211 is an equidigital number, since it uses as much as digits as its factorization.

21001210211 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21001210211 its reverse (11201210012), we get a palindrome (32202420223).

The spelling of 21001210211 in words is "twenty-one billion, one million, two hundred ten thousand, two hundred eleven".