6504404661 has 6 divisors (see below), whose sum is σ = 9395251190. Its totient is φ = 4336269768.

The previous prime is 6504404611. The next prime is 6504404719. The reversal of 6504404661 is 1664044056.

It can be written as a sum of positive squares in only one way, i.e., 6271689636 + 232715025 = 79194^2 + 15255^2 .

It is not a de Polignac number, because 6504404661 - 2¹¹ = 6504402613 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6504404611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 361355806 + ... + 361355823.

Almost surely, 2^6504404661 is an apocalyptic number.

It is an amenable number.

6504404661 is a deficient number, since it is larger than the sum of its proper divisors (2890846529).

6504404661 is a wasteful number, since it uses less digits than its factorization.

6504404661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 722711635 (or 722711632 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The square root of 6504404661 is about 80649.8894047599. The cubic root of 6504404661 is about 1866.6770331305.

The spelling of 6504404661 in words is "six billion, five hundred four million, four hundred four thousand, six hundred sixty-one".