21243411053 has 2 divisors, whose sum is σ = 21243411054. Its totient is φ = 21243411052.

The previous prime is 21243411047. The next prime is 21243411061. The reversal of 21243411053 is 35011434212.

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., 15280173769 + 5963237284 = 123613^2 + 77222^2 .

It is a cyclic number.

It is not a de Polignac number, because 21243411053 - 2²⁴ = 21226633837 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21243411653) 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, 10621705526 + 10621705527.

It is an arithmetic number, because the mean of its divisors is an integer number (10621705527).

Almost surely, 2^21243411053 is an apocalyptic number.

It is an amenable number.

21243411053 is a deficient number, since it is larger than the sum of its proper divisors (1).

21243411053 is an equidigital number, since it uses as much as digits as its factorization.

21243411053 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2880, while the sum is 26.

Adding to 21243411053 its reverse (35011434212), we get a palindrome (56254845265).

The spelling of 21243411053 in words is "twenty-one billion, two hundred forty-three million, four hundred eleven thousand, fifty-three".