64660778512 has 20 divisors (see below), whose sum is σ = 136669373136. Its totient is φ = 29391262880.

The previous prime is 64660778503. The next prime is 64660778521. The reversal of 64660778512 is 21587706646.

It is an interprime number because it is at equal distance from previous prime (64660778503) and next prime (64660778521).

It is a self number, because there is not a number n which added to its sum of digits gives 64660778512.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 183695218 + ... + 183695569.

Almost surely, 2^64660778512 is an apocalyptic number.

It is an amenable number.

64660778512 is an abundant number, since it is smaller than the sum of its proper divisors (72008594624).

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

64660778512 is a wasteful number, since it uses less digits than its factorization.

64660778512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 367390806 (or 367390800 counting only the distinct ones).

The product of its (nonzero) digits is 3386880, while the sum is 52.

The spelling of 64660778512 in words is "sixty-four billion, six hundred sixty million, seven hundred seventy-eight thousand, five hundred twelve".