21115230013 has 2 divisors, whose sum is σ = 21115230014. Its totient is φ = 21115230012.

The previous prime is 21115229957. The next prime is 21115230061. The reversal of 21115230013 is 31003251112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18070618329 + 3044611684 = 134427^2 + 55178^2 .

It is a cyclic number.

It is not a de Polignac number, because 21115230013 - 2⁹ = 21115229501 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21115230083) 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, 10557615006 + 10557615007.

It is an arithmetic number, because the mean of its divisors is an integer number (10557615007).

Almost surely, 2^21115230013 is an apocalyptic number.

It is an amenable number.

21115230013 is a deficient number, since it is larger than the sum of its proper divisors (1).

21115230013 is an equidigital number, since it uses as much as digits as its factorization.

21115230013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 180, while the sum is 19.

Adding to 21115230013 its reverse (31003251112), we get a palindrome (52118481125).

It can be divided in two parts, 211152 and 30013, that added together give a triangular number (241165 = T₆₉₄).

The spelling of 21115230013 in words is "twenty-one billion, one hundred fifteen million, two hundred thirty thousand, thirteen".