657986656 has 48 divisors (see below), whose sum is σ = 1349913600. Its totient is φ = 315354240.

The previous prime is 657986647. The next prime is 657986657. The reversal of 657986656 is 656689756.

It is a self number, because there is not a number n which added to its sum of digits gives 657986656.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (657986657) 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 7 ways as a sum of consecutive naturals, for example, 103045 + ... + 109243.

It is an arithmetic number, because the mean of its divisors is an integer number (28123200).

Almost surely, 2^657986656 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 657986656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (674956800).

657986656 is an abundant number, since it is smaller than the sum of its proper divisors (691926944).

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

657986656 is a wasteful number, since it uses less digits than its factorization.

657986656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6347 (or 6339 counting only the distinct ones).

The product of its digits is 16329600, while the sum is 58.

The square root of 657986656 is about 25651.2505738024. The cubic root of 657986656 is about 869.7725463439.

The spelling of 657986656 in words is "six hundred fifty-seven million, nine hundred eighty-six thousand, six hundred fifty-six".