64665916791 has 16 divisors (see below), whose sum is σ = 98561030400. Its totient is φ = 36943518528.

The previous prime is 64665916759. The next prime is 64665916801. The reversal of 64665916791 is 19761956646.

It is not a de Polignac number, because 64665916791 - 2⁵ = 64665916759 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64665916291) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 256621 + ... + 441798.

It is an arithmetic number, because the mean of its divisors is an integer number (6160064400).

Almost surely, 2^64665916791 is an apocalyptic number.

64665916791 is a deficient number, since it is larger than the sum of its proper divisors (33895113609).

64665916791 is a wasteful number, since it uses less digits than its factorization.

64665916791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 702838.

The product of its digits is 14696640, while the sum is 60.

The spelling of 64665916791 in words is "sixty-four billion, six hundred sixty-five million, nine hundred sixteen thousand, seven hundred ninety-one".