64646775648 has 576 divisors, whose sum is σ = 246527608320. Its totient is φ = 16305214464.

The previous prime is 64646775643. The next prime is 64646775659. The reversal of 64646775648 is 84657764646.

It is a happy number.

64646775648 is a `hidden beast` number, since 6 + 4 + 6 + 4 + 67 + 7 + 564 + 8 = 666.

64646775648 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64646775643) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 12655911 + ... + 12661017.

It is an arithmetic number, because the mean of its divisors is an integer number (427999320).

Almost surely, 2^64646775648 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64646775648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (123263804160).

64646775648 is an abundant number, since it is smaller than the sum of its proper divisors (181880832672).

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

64646775648 is a wasteful number, since it uses less digits than its factorization.

64646775648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5176 (or 5155 counting only the distinct ones).

The product of its digits is 162570240, while the sum is 63.

The spelling of 64646775648 in words is "sixty-four billion, six hundred forty-six million, seven hundred seventy-five thousand, six hundred forty-eight".