import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.math.BigInteger;
import java.util.HashMap;
import java.util.Map;

public class Main {
	public static void main(String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int q = Integer.parseInt(br.readLine());
		int mod = 998244353;
		Eratosthenes era = new Eratosthenes(100000);
		Kaijou kai = new Kaijou(2000000, mod);

		int cnt = 0;
		PrintWriter pw = new PrintWriter(System.out);
		for (int i = 0; i < q; i++) {
			String[] sa = br.readLine().split(" ");
			int a = Integer.parseInt(sa[0]);
			int b = Integer.parseInt(sa[1]);

			Map<Integer, Integer> map = era.bunkai(a);
			for (int v : map.values()) {
				cnt += v;
			}
			pw.println(kai.comb(cnt - 1, b - 1));
		}
		pw.flush();
		br.close();
	}

	static class Eratosthenes {
		int[] div;

		public Eratosthenes(int n) {
			div = new int[n + 1];
			if (n < 2) return;
			div[0] = -1;
			div[1] = -1;
			int end = (int) Math.sqrt(n) + 1;
			for (int i = 2; i <= end; i++) {
				if (div[i] == 0) {
					div[i] = i;
					for (int j = i * i; j <= n; j+=i) {
						if (div[j] == 0) div[j] = i;
					}
				}
			}
			for (int i = end + 1; i <= n; i++) {
				if (div[i] == 0) div[i] = i;
			}
		}

		public Map<Integer, Integer> bunkai(int x) {
			Map<Integer, Integer> soinsu = new HashMap<>();
			while (x > 1) {
				Integer d = div[x];
				soinsu.put(d, soinsu.getOrDefault(d, 0) + 1);
				x /= d;
			}
			return soinsu;
		}

		public boolean isSosuu(int x) {
			return div[x] == x;
		}
	}

	static class Kaijou {
		long[] p, pi;
		int m;

		public Kaijou(int n, int mod) {
			n++;
			m = mod;
			p = new long[n];
			pi = new long[n];
			p[0] = 1;
			pi[0] = 1;
			for (int i = 1; i < n; i++) {
				p[i] = p[i - 1] * i % m;
			}
			pi[n - 1] = BigInteger.valueOf(p[n - 1])
					.modInverse(BigInteger.valueOf(m)).longValue();
			for (int i = n - 1; i > 1; i--) {
				pi[i - 1] = pi[i] * i % m;
			}
		}

		public long comb(int n, int r) {
			if (n < r) return 0;
			return p[n] * pi[r] % m * pi[n - r] % m;
		}

		public long perm(int n, int r) {
			if (n < r) return 0;
			return p[n] * pi[n - r] % m;
		}
	}
}