This number is the period, in pi units, of e to the quantity i x over two.
This number is the period, in pi units, of e to the quantity i x over two. Any number can be expressed as the sum of this many integer squares. This number is the highest degree polynomial generally solvable by an algebraic equation. The only Platonic solid with an equal number of vertices and faces has this many of each. If the last two digits of a number are (*) divisible by this number, then that number is divisible by this number. It is the smallest non-prime number and the only one whose prime factors are equal both when multiplied and when added. For 10 points, identify this number of vertices of a tetrahedron and the number of sides of a square.
This number is the period, in pi units, of e to the quantity i x over two.
{four}