656684 has 24 divisors (see below), whose sum is σ = 1344000. Its totient is φ = 274896.

The previous prime is 656683. The next prime is 656687. The reversal of 656684 is 486656.

It is not an unprimeable number, because it can be changed into a prime (656681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1067 + ... + 1565.

It is an arithmetic number, because the mean of its divisors is an integer number (56000).

2⁶⁵⁶⁶⁸⁴ 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 656684, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (672000).

656684 is an abundant number, since it is smaller than the sum of its proper divisors (687316).

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

656684 is a wasteful number, since it uses less digits than its factorization.

656684 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 557 (or 555 counting only the distinct ones).

The product of its digits is 34560, while the sum is 35.

The square root of 656684 is about 810.3604136432. The cubic root of 656684 is about 86.9198186698.

The spelling of 656684 in words is "six hundred fifty-six thousand, six hundred eighty-four".