64 (number) it is possible to find sequences of 64 consecutive integers such that each inner member shares a factor with either the first or the last member, 64 is an Erdős–Woods number. In base 10, no integer added up to its own digits yields 64, hence it is a self number. 64 is a superperfect number—a number such that σ(σ("n")) = 2"n". 64 is the index of Graham's number in the rapidly growing sequence 3↑↑↑↑3, 3 ↑ 3,… Sixty-four is: 64 (number) 64 (sixty-four) is the natural number following 63 and preceding 65. Sixty-four is the square of 8, the cube
Squaring the square squaring the square: that is, given a cube "C", the problem of dividing it into finitely many smaller cubes, no two congruent. Unlike the case of squaring the square, a hard yet solvable problem, there is no perfect cubed cube and, more generally, no dissection of a rectangular cuboid "C" into a finite number of unequal cubes. Suppose that there is such a dissection. Make a face of "C" its horizontal base. The base is divided into a perfect squared rectangle "R" by the cubes which rest on it. Each corner square of "R" has a smaller adjacent edge square,