656318068544 has 84 divisors (see below), whose sum is σ = 1353475541964. Its totient is φ = 315754242048.

The previous prime is 656318068543. The next prime is 656318068561. The reversal of 656318068544 is 445860813656.

It can be written as a sum of positive squares in 6 ways, for example, as 264492146944 + 391825921600 = 514288^2 + 625960^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 656318068544.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (656318068543) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15749624 + ... + 15791240.

It is an arithmetic number, because the mean of its divisors is an integer number (16112804071).

Almost surely, 2^656318068544 is an apocalyptic number.

656318068544 is a gapful number since it is divisible by the number (64) 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 656318068544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (676737770982).

656318068544 is an abundant number, since it is smaller than the sum of its proper divisors (697157473420).

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

656318068544 is a wasteful number, since it uses less digits than its factorization.

656318068544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41980 (or 41941 counting only the distinct ones).

The product of its (nonzero) digits is 16588800, while the sum is 56.

The spelling of 656318068544 in words is "six hundred fifty-six billion, three hundred eighteen million, sixty-eight thousand, five hundred forty-four".