64513615665 has 16 divisors (see below), whose sum is σ = 103228587648. Its totient is φ = 34404994176.

The previous prime is 64513615627. The next prime is 64513615679. The reversal of 64513615665 is 56651631546.

It is not a de Polignac number, because 64513615665 - 2²⁰ = 64512567089 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 107629 + ... + 374981.

It is an arithmetic number, because the mean of its divisors is an integer number (6451786728).

Almost surely, 2^64513615665 is an apocalyptic number.

It is an amenable number.

64513615665 is a deficient number, since it is larger than the sum of its proper divisors (38714971983).

64513615665 is a wasteful number, since it uses less digits than its factorization.

64513615665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 283448.

The product of its digits is 1944000, while the sum is 48.

The spelling of 64513615665 in words is "sixty-four billion, five hundred thirteen million, six hundred fifteen thousand, six hundred sixty-five".