64665656646 has 16 divisors (see below), whose sum is σ = 129744516144. Its totient is φ = 21486351744.

The previous prime is 64665656633. The next prime is 64665656681.

64665656646 is nontrivially palindromic in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 64665656646.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17214751 + ... + 17218506.

It is an arithmetic number, because the mean of its divisors is an integer number (8109032259).

Almost surely, 2^64665656646 is an apocalyptic number.

64665656646 is an abundant number, since it is smaller than the sum of its proper divisors (65078859498).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

64665656646 is a wasteful number, since it uses less digits than its factorization.

64665656646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34433575.

The product of its digits is 111974400, while the sum is 60.

The spelling of 64665656646 in words is "sixty-four billion, six hundred sixty-five million, six hundred fifty-six thousand, six hundred forty-six".