21212122011211 has 2 divisors, whose sum is σ = 21212122011212. Its totient is φ = 21212122011210.

The previous prime is 21212122011203. The next prime is 21212122011239. The reversal of 21212122011211 is 11211022121212.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21212122011211 - 2³ = 21212122011203 is a prime.

It is not a weakly prime, because it can be changed into another prime (21212122011251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606061005605 + 10606061005606.

It is an arithmetic number, because the mean of its divisors is an integer number (10606061005606).

Almost surely, 2^{21212122011211} is an apocalyptic number.

21212122011211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21212122011211 is an equidigital number, since it uses as much as digits as its factorization.

21212122011211 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 21212122011211 its reverse (11211022121212), we get a palindrome (32423144132423).

The spelling of 21212122011211 in words is "twenty-one trillion, two hundred twelve billion, one hundred twenty-two million, eleven thousand, two hundred eleven".