Determines if one number (x) is an even power of a given base. Check out http://cwestblog.com/2018/03/20/javascript-snippet-ispowerof-x-base/

isPowerOf.js

/**
 * @preserve isPowerOf() by Chris West
 * http://cwestblog.com/2018/03/20/javascript-snippet-ispowerof-x-base/
 *
 * Determines if one number (x) is an even power of a given base.
 * @name isPowerOf
 * @function
 * @param {number} x
 *   Number that could be the result of multiplying or dividing base
 *   by itself a certain number of times.
 * @param {number} base
 *   Number that will be checked to see if it is the base that when
 *   multiplied or divided by itself a certain amount of times will
 *   result in x.
 * @returns {boolean}
 *   Returns `true` if when base is multiplied or divided by itself
 *   a certain number of times it will result in x.
 */
function isPowerOf(x, base) {
  x = Math.log(x) / Math.log(base);
  return x === ~~x;
}