16565505420643 has 2 divisors, whose sum is σ = 16565505420644. Its totient is φ = 16565505420642.

The previous prime is 16565505420619. The next prime is 16565505420647. The reversal of 16565505420643 is 34602450556561.

16565505420643 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16565505420643 is a prime.

It is not a weakly prime, because it can be changed into another prime (16565505420647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8282752710321 + 8282752710322.

It is an arithmetic number, because the mean of its divisors is an integer number (8282752710322).

Almost surely, 2^{16565505420643} is an apocalyptic number.

16565505420643 is a deficient number, since it is larger than the sum of its proper divisors (1).

16565505420643 is an equidigital number, since it uses as much as digits as its factorization.

16565505420643 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12960000, while the sum is 52.

The spelling of 16565505420643 in words is "sixteen trillion, five hundred sixty-five billion, five hundred five million, four hundred twenty thousand, six hundred forty-three".