64640648368 has 40 divisors (see below), whose sum is σ = 129038044608. Its totient is φ = 31352681472.

The previous prime is 64640648351. The next prime is 64640648393. The reversal of 64640648368 is 86384604646.

It is a happy number.

It is a Smith number, since the sum of its digits (55) coincides with the sum of the digits of its prime factors.

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, 295371 + ... + 465322.

Almost surely, 2^64640648368 is an apocalyptic number.

It is an amenable number.

64640648368 is a deficient number, since it is larger than the sum of its proper divisors (64397396240).

64640648368 is a wasteful number, since it uses less digits than its factorization.

64640648368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 760861 (or 760855 counting only the distinct ones).

The product of its (nonzero) digits is 15925248, while the sum is 55.

The spelling of 64640648368 in words is "sixty-four billion, six hundred forty million, six hundred forty-eight thousand, three hundred sixty-eight".