21123310132013 has 2 divisors, whose sum is σ = 21123310132014. Its totient is φ = 21123310132012.

The previous prime is 21123310132007. The next prime is 21123310132021. The reversal of 21123310132013 is 31023101332112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19688149259689 + 1435160872324 = 4437133^2 + 1197982^2 .

It is a cyclic number.

It is not a de Polignac number, because 21123310132013 - 2⁴ = 21123310131997 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21123310132013.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21123310132033) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10561655066006 + 10561655066007.

It is an arithmetic number, because the mean of its divisors is an integer number (10561655066007).

Almost surely, 2^{21123310132013} is an apocalyptic number.

It is an amenable number.

21123310132013 is a deficient number, since it is larger than the sum of its proper divisors (1).

21123310132013 is an equidigital number, since it uses as much as digits as its factorization.

21123310132013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 23.

Adding to 21123310132013 its reverse (31023101332112), we get a palindrome (52146411464125).

The spelling of 21123310132013 in words is "twenty-one trillion, one hundred twenty-three billion, three hundred ten million, one hundred thirty-two thousand, thirteen".