664837056 has 168 divisors, whose sum is σ = 2160696720. Its totient is φ = 193757184.

The previous prime is 664837021. The next prime is 664837111. The reversal of 664837056 is 650738466.

It is a super-2 number, since 2×664837056² = 884016622061494272, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 139936 + ... + 144608.

It is an arithmetic number, because the mean of its divisors is an integer number (12861290).

Almost surely, 2^664837056 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 664837056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1080348360).

664837056 is an abundant number, since it is smaller than the sum of its proper divisors (1495859664).

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

664837056 is a wasteful number, since it uses less digits than its factorization.

664837056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4723 (or 4710 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 45.

The square root of 664837056 is about 25784.4343742499. The cubic root of 664837056 is about 872.7805764791.

The spelling of 664837056 in words is "six hundred sixty-four million, eight hundred thirty-seven thousand, fifty-six".