6565665647 has 2 divisors, whose sum is σ = 6565665648. Its totient is φ = 6565665646.

The previous prime is 6565665619. The next prime is 6565665661. The reversal of 6565665647 is 7465665656.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 6565665647 - 2⁸ = 6565665391 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 6565665592 and 6565665601.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6565665607) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3282832823 + 3282832824.

It is an arithmetic number, because the mean of its divisors is an integer number (3282832824).

Almost surely, 2^6565665647 is an apocalyptic number.

6565665647 is a deficient number, since it is larger than the sum of its proper divisors (1).

6565665647 is an equidigital number, since it uses as much as digits as its factorization.

6565665647 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27216000, while the sum is 56.

The square root of 6565665647 is about 81028.7951718400. The cubic root of 6565665647 is about 1872.5190912865.

Subtracting 6565665647 from its reverse (7465665656), we obtain a palindrome (900000009).

The spelling of 6565665647 in words is "six billion, five hundred sixty-five million, six hundred sixty-five thousand, six hundred forty-seven".