6656 has 20 divisors (see below), whose sum is σ = 14322. Its totient is φ = 3072.

The previous prime is 6653. The next prime is 6659. The reversal of 6656 is 6566.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (6653) and next prime (6659).

It can be written as a sum of positive squares in only one way, i.e., 6400 + 256 = 80^2 + 16^2 .

Its product of digits (1080) is a multiple of the sum of its prime divisors (15).

It is not an unprimeable number, because it can be changed into a prime (6653) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (3) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 506 + ... + 518.

2⁶⁶⁵⁶ 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 6656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7161).

6656 is an abundant number, since it is smaller than the sum of its proper divisors (7666).

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

6656 is an equidigital number, since it uses as much as digits as its factorization.

6656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31 (or 15 counting only the distinct ones).

The product of its digits is 1080, while the sum is 23.

The square root of 6656 is about 81.5843122175. The cubic root of 6656 is about 18.8106775018.

The spelling of 6656 in words is "six thousand, six hundred fifty-six".