64 (number) 64 (number) 64 (sixty-four) is the natural number following 63 and preceding 65. Sixty-four is the square of 8, the cube of 4, and the sixth power of 2. It is the smallest number with exactly seven divisors. It is the lowest positive power of two that is adjacent to neither a Mersenne prime nor a Fermat prime. 64 is the sum of Euler's totient function for the first fourteen integers. It is also a dodecagonal number and a centered triangular number. 64 is also the first whole number that is both a perfect square and a perfect cube. Since
Unit cube unit hypercube of "n" dimensions is formula_1, the square root of "n" and the (Euclidean) length of the vector (1,1,1...1,1) in "n"-dimensional space. Unit cube A unit cube, more formally a cube of side 1, is a cube whose sides are 1 unit long. The volume of a 3-dimensional unit cube is 1 cubic unit, and its total surface area is 6 square units. The term "unit cube" or unit hypercube is also used for hypercubes, or "cubes" in "n"-dimensional spaces, for values of "n" other than 3 and edge length 1. Sometimes the term "unit cube" refers in specific