664388904960 has 1728 divisors, whose sum is σ = 2785459622400. Its totient is φ = 150493593600.

The previous prime is 664388904953. The next prime is 664388904961. The reversal of 664388904960 is 69409883466.

664388904960 is a `hidden beast` number, since 6 + 64 + 3 + 8 + 89 + 0 + 496 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1728).

It is not an unprimeable number, because it can be changed into a prime (664388904961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 21431900145 + ... + 21431900175.

It is an arithmetic number, because the mean of its divisors is an integer number (1611955800).

Almost surely, 2^664388904960 is an apocalyptic number.

664388904960 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664388904960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1392729811200).

664388904960 is an abundant number, since it is smaller than the sum of its proper divisors (2121070717440).

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

664388904960 is an equidigital number, since it uses as much as digits as its factorization.

664388904960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122 (or 81 counting only the distinct ones).

The product of its (nonzero) digits is 53747712, while the sum is 63.

The spelling of 664388904960 in words is "six hundred sixty-four billion, three hundred eighty-eight million, nine hundred four thousand, nine hundred sixty".