6505610656809 has 24 divisors (see below), whose sum is σ = 9547508676160. Its totient is φ = 3937370801760.

The previous prime is 6505610656709. The next prime is 6505610656829. The reversal of 6505610656809 is 9086560165056.

It is a happy number.

It is not a de Polignac number, because 6505610656809 - 2⁸ = 6505610656553 is a prime.

It is a Smith number, since the sum of its digits (57) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (6505610656829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12061954 + ... + 12589755.

Almost surely, 2^{6505610656809} is an apocalyptic number.

It is an amenable number.

6505610656809 is a deficient number, since it is larger than the sum of its proper divisors (3041898019351).

6505610656809 is a wasteful number, since it uses less digits than its factorization.

6505610656809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24652461 (or 24652450 counting only the distinct ones).

The product of its (nonzero) digits is 11664000, while the sum is 57.

The spelling of 6505610656809 in words is "six trillion, five hundred five billion, six hundred ten million, six hundred fifty-six thousand, eight hundred nine".