664633644960 has 96 divisors (see below), whose sum is σ = 2093790347712. Its totient is φ = 177219184640.

The previous prime is 664633644901. The next prime is 664633644973. The reversal of 664633644960 is 69446336466.

It is a tau number, because it is divible by the number of its divisors (96).

It is a self number, because there is not a number n which added to its sum of digits gives 664633644960.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5637820 + ... + 5754500.

It is an arithmetic number, because the mean of its divisors is an integer number (21810316122).

Almost surely, 2^664633644960 is an apocalyptic number.

664633644960 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

664633644960 is an abundant number, since it is smaller than the sum of its proper divisors (1429156702752).

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

664633644960 is a wasteful number, since it uses less digits than its factorization.

664633644960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128566 (or 128558 counting only the distinct ones).

The product of its (nonzero) digits is 40310784, while the sum is 57.

The spelling of 664633644960 in words is "six hundred sixty-four billion, six hundred thirty-three million, six hundred forty-four thousand, nine hundred sixty".