663682656 has 144 divisors (see below), whose sum is σ = 2182695984. Its totient is φ = 175021056.

The previous prime is 663682619. The next prime is 663682667. The reversal of 663682656 is 656286366.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

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 23 ways as a sum of consecutive naturals, for example, 55726 + ... + 66578.

It is an arithmetic number, because the mean of its divisors is an integer number (15157611).

Almost surely, 2^663682656 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 663682656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1091347992).

663682656 is an abundant number, since it is smaller than the sum of its proper divisors (1519013328).

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

663682656 is a wasteful number, since it uses less digits than its factorization.

663682656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10893 (or 10878 counting only the distinct ones).

The product of its digits is 1866240, while the sum is 48.

The square root of 663682656 is about 25762.0390497336. The cubic root of 663682656 is about 872.2751285137.

The spelling of 663682656 in words is "six hundred sixty-three million, six hundred eighty-two thousand, six hundred fifty-six".