21044143543 has 2 divisors, whose sum is σ = 21044143544. Its totient is φ = 21044143542.

The previous prime is 21044143531. The next prime is 21044143559. The reversal of 21044143543 is 34534144012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21044143543 - 2⁵ = 21044143511 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21044143343) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10522071771 + 10522071772.

It is an arithmetic number, because the mean of its divisors is an integer number (10522071772).

Almost surely, 2^21044143543 is an apocalyptic number.

21044143543 is a deficient number, since it is larger than the sum of its proper divisors (1).

21044143543 is an equidigital number, since it uses as much as digits as its factorization.

21044143543 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23040, while the sum is 31.

Adding to 21044143543 its reverse (34534144012), we get a palindrome (55578287555).

The spelling of 21044143543 in words is "twenty-one billion, forty-four million, one hundred forty-three thousand, five hundred forty-three".