21111111111313 has 2 divisors, whose sum is σ = 21111111111314. Its totient is φ = 21111111111312.

The previous prime is 21111111111283. The next prime is 21111111111317. The reversal of 21111111111313 is 31311111111112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21089843847424 + 21267263889 = 4592368^2 + 145833^2 .

It is a cyclic number.

It is not a de Polignac number, because 21111111111313 - 2⁵ = 21111111111281 is a prime.

It is not a weakly prime, because it can be changed into another prime (21111111111317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555555555656 + 10555555555657.

It is an arithmetic number, because the mean of its divisors is an integer number (10555555555657).

Almost surely, 2^{21111111111313} is an apocalyptic number.

It is an amenable number.

21111111111313 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111111111313 is an equidigital number, since it uses as much as digits as its factorization.

21111111111313 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18, while the sum is 19.

Adding to 21111111111313 its reverse (31311111111112), we get a palindrome (52422222222425).

The spelling of 21111111111313 in words is "twenty-one trillion, one hundred eleven billion, one hundred eleven million, one hundred eleven thousand, three hundred thirteen".