664001968 has 40 divisors (see below), whose sum is σ = 1547678720. Its totient is φ = 269593920.

The previous prime is 664001903. The next prime is 664001983. The reversal of 664001968 is 869100466.

It is a super-3 number, since 3×664001968³ (a number of 27 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a self number, because there is not a number n which added to its sum of digits gives 664001968.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 153888 + ... + 158143.

It is an arithmetic number, because the mean of its divisors is an integer number (38691968).

Almost surely, 2^664001968 is an apocalyptic number.

It is an amenable number.

664001968 is an abundant number, since it is smaller than the sum of its proper divisors (883676752).

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

664001968 is a wasteful number, since it uses less digits than its factorization.

664001968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 312065 (or 312059 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 40.

The square root of 664001968 is about 25768.2356400278. The cubic root of 664001968 is about 872.4149961932.

The spelling of 664001968 in words is "six hundred sixty-four million, one thousand, nine hundred sixty-eight".