21243034313 has 2 divisors, whose sum is σ = 21243034314. Its totient is φ = 21243034312.

The previous prime is 21243034273. The next prime is 21243034321. The reversal of 21243034313 is 31343034212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21058943689 + 184090624 = 145117^2 + 13568^2 .

It is a cyclic number.

It is not a de Polignac number, because 21243034313 - 2⁶ = 21243034249 is a prime.

It is not a weakly prime, because it can be changed into another prime (21243034333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10621517156 + 10621517157.

It is an arithmetic number, because the mean of its divisors is an integer number (10621517157).

Almost surely, 2^21243034313 is an apocalyptic number.

It is an amenable number.

21243034313 is a deficient number, since it is larger than the sum of its proper divisors (1).

21243034313 is an equidigital number, since it uses as much as digits as its factorization.

21243034313 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5184, while the sum is 26.

Adding to 21243034313 its reverse (31343034212), we get a palindrome (52586068525).

The spelling of 21243034313 in words is "twenty-one billion, two hundred forty-three million, thirty-four thousand, three hundred thirteen".