664856064 has 120 divisors (see below), whose sum is σ = 1933142640. Its totient is φ = 219967488.

The previous prime is 664856053. The next prime is 664856069. The reversal of 664856064 is 460658466.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664856069) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 722997 + ... + 723915.

It is an arithmetic number, because the mean of its divisors is an integer number (16109522).

Almost surely, 2^664856064 is an apocalyptic number.

664856064 is a gapful number since it is divisible by the number (64) 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 664856064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (966571320).

664856064 is an abundant number, since it is smaller than the sum of its proper divisors (1268286576).

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

664856064 is a wasteful number, since it uses less digits than its factorization.

664856064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1100 (or 1081 counting only the distinct ones).

The product of its (nonzero) digits is 829440, while the sum is 45.

The square root of 664856064 is about 25784.8029660884. The cubic root of 664856064 is about 872.7888941338.

The spelling of 664856064 in words is "six hundred sixty-four million, eight hundred fifty-six thousand, sixty-four".