function main(input){
	var x = 2, y = Number(input), z, a = x * y;
	if (x < y) [x, y] = [y, x];

	z = x % y;
	while (z !== 0) {
		x = y;
		y = z;
		z = x % y;
	}

	console.log(a/y);
}

main(require("fs").readFileSync("/dev/stdin", "utf8"));