21352507543 has 2 divisors, whose sum is σ = 21352507544. Its totient is φ = 21352507542.

The previous prime is 21352507531. The next prime is 21352507613. The reversal of 21352507543 is 34570525312.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21352507543 - 2⁹ = 21352507031 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21352507523) 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, 10676253771 + 10676253772.

It is an arithmetic number, because the mean of its divisors is an integer number (10676253772).

Almost surely, 2^21352507543 is an apocalyptic number.

21352507543 is a deficient number, since it is larger than the sum of its proper divisors (1).

21352507543 is an equidigital number, since it uses as much as digits as its factorization.

21352507543 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 126000, while the sum is 37.

The spelling of 21352507543 in words is "twenty-one billion, three hundred fifty-two million, five hundred seven thousand, five hundred forty-three".