656544445656 has 256 divisors, whose sum is σ = 1907371929600. Its totient is φ = 186234048000.

The previous prime is 656544445651. The next prime is 656544445679.

656544445656 is nontrivially palindromic in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 656544445656.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (656544445651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 327779551 + ... + 327781553.

It is an arithmetic number, because the mean of its divisors is an integer number (7450671600).

Almost surely, 2^656544445656 is an apocalyptic number.

656544445656 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 656544445656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (953685964800).

656544445656 is an abundant number, since it is smaller than the sum of its proper divisors (1250827483944).

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

656544445656 is a wasteful number, since it uses less digits than its factorization.

656544445656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2790 (or 2786 counting only the distinct ones).

The product of its digits is 207360000, while the sum is 60.

The spelling of 656544445656 in words is "six hundred fifty-six billion, five hundred forty-four million, four hundred forty-five thousand, six hundred fifty-six".