21111211211113 has 2 divisors, whose sum is σ = 21111211211114. Its totient is φ = 21111211211112.

The previous prime is 21111211211099. The next prime is 21111211211141. The reversal of 21111211211113 is 31111211211112.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12484936760409 + 8626274450704 = 3533403^2 + 2937052^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21111211211113 is a prime.

It is not a weakly prime, because it can be changed into another prime (21111211211143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555605605556 + 10555605605557.

It is an arithmetic number, because the mean of its divisors is an integer number (10555605605557).

Almost surely, 2^{21111211211113} is an apocalyptic number.

It is an amenable number.

21111211211113 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111211211113 is an equidigital number, since it uses as much as digits as its factorization.

21111211211113 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24, while the sum is 19.

Adding to 21111211211113 its reverse (31111211211112), we get a palindrome (52222422422225).

Subtracting 21111211211113 from its reverse (31111211211112), we obtain a palindrome (9999999999999).

The spelling of 21111211211113 in words is "twenty-one trillion, one hundred eleven billion, two hundred eleven million, two hundred eleven thousand, one hundred thirteen".