function Main(input) {
    const [[N, W], X, Y] = input.split("\n").map(e => e.split(" ").map(Number));

    const max = 2e5;
    let price = [...new Array(max + 1).fill(0)];

    for (let i = 0; i < N; i++) {
        const set = new Set();
        const num = X[i];
        for (let j = 1; j <= Math.sqrt(num); j++) {
            if (num % j === 0) {
                set.add(j);
                set.add(num / j);
            }
        }
        for (const v of [...set]) {
            price[v] += Y[i];
        }
    }

    let ans = 0;
    for (let i = W; i <= max; i++) {
        ans = Math.max(price[i], ans);
    }

    console.log(ans);
}
Main(require("fs").readFileSync(0)+"")