6515655561 has 12 divisors (see below), whose sum is σ = 9469243888. Its totient is φ = 4317120504.

The previous prime is 6515655551. The next prime is 6515655581. The reversal of 6515655561 is 1655565156.

It is not a de Polignac number, because 6515655561 - 2⁵ = 6515655529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6515655551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2219275 + ... + 2222208.

Almost surely, 2^6515655561 is an apocalyptic number.

It is an amenable number.

6515655561 is a deficient number, since it is larger than the sum of its proper divisors (2953588327).

6515655561 is a wasteful number, since it uses less digits than its factorization.

6515655561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4441652 (or 4441649 counting only the distinct ones).

The product of its digits is 675000, while the sum is 45.

The square root of 6515655561 is about 80719.6107584768. The cubic root of 6515655561 is about 1867.7526990402.

The spelling of 6515655561 in words is "six billion, five hundred fifteen million, six hundred fifty-five thousand, five hundred sixty-one".