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| #include <bits/stdc++.h> using namespace std; namespace Legendgod { namespace Read {
#ifdef Fread const int Siz = (1 << 21) + 5; char *iS, *iT, buf[Siz]; #define gc() ( iS == iT ? (iT = (iS = buf) + fread(buf, 1, Siz, stdin), iS == iT ? EOF : *iS ++) : *iS ++ ) #define getchar gc #endif template <typename T> void r1(T &x) { x = 0; char c(getchar()); int f(1); for(; !isdigit(c); c = getchar()) if(c == '-') f = -1; for(; isdigit(c); c = getchar()) x = (x << 1) + (x << 3) + (c ^ 48); x *= f; } template <typename T, typename...Args> void r1(T &x, Args&...arg) { r1(x), r1(arg...); } #undef getchar }
using namespace Read;
#define int long long typedef long long int64; typedef unsigned long long uint64; const int maxn = 1e7 + 5; const int64 mod0 = 1e9 + 7, mod1 = mod0 * mod0; int64 mod = 1e9 + 7;
int64 n, m, A;
bitset<maxn> vis; int pr[664579 + 5], tot(0), mu[maxn];
void init(int x) { vis.reset(); mu[1] = 1; for(int i = 2; i <= x; ++ i) { if(!vis[i]) pr[++ tot] = i, mu[i] = - 1; for(int64 j = 1, k; k = 1ll * pr[j] * i, k <= x && j <= tot; ++ j) { vis[k] = 1; if(!(i % pr[j])) break; mu[k] = - mu[i]; } } for(int i = 1; i <= x; ++ i) mu[i] += mu[i - 1]; }
int pd;
int64 Mul(int64 a,int64 b) { long double res = (long double) a * b / mod; int64 tmp = a * b, t1 = (tmp - (uint64)res * mod + mod) % mod; return t1; }
int64 ksm(int64 x,int64 mi) { mi %= (mod - 1); int64 res(1); while(mi) { if(mi & 1) res = Mul(res, x); mi >>= 1; x = Mul(x, x); } return res; }
void exgcd(int64 a, int64 b, int64 &x,int64 &y) { if(b == 0) return x = 1, y = 0, void(); exgcd(b, a % b, x, y); int64 z = y; y = x - a / b * y, x = z; }
int64 Inv(int64 c, int64 md) { int64 x, y; exgcd(c, mod, x, y); return x; }
void Solvem() { m = 0; for(int64 i = 1, last; i <= A; i = last + 1) { last = min(A, A / (A / i)); int64 tmp = A / last, tmp1 = mu[last] - mu[i - 1]; m = (m + Mul(Mul(Mul(tmp, tmp), tmp), tmp1)) % mod; m = (m + Mul(3, Mul(Mul(tmp, tmp), tmp1))) % mod; } m = (m + 2) % mod; int64 iv = Inv(6, mod); m = Mul(m, iv);
m = (m + mod) % mod; }
int64 F(int64 n) { int64 tmp = ksm(m - 1, n) + (n & 1 ? -1 : 1) * (m - 1); tmp = (tmp + mod) % mod; return tmp; }
int up[50], ps[50], ed;
void pre(int64 n) { ed = 0; for(int i = 1; i <= tot && pr[i] <= n; ++ i) if(n % pr[i] == 0) { up[++ ed] = pr[i], ps[ed] = 0; while(!(n % pr[i])) ++ ps[ed], n /= pr[i]; } if(n != 1) up[++ ed] = n, ps[ed] = 1;
}
int64 ans(0);
void dfs(int dep, int64 d, int64 phi) { if(dep == ed + 1) { ans = (ans + Mul(phi, F(n / d))) % mod; return ; } dfs(dep + 1, d, phi); d *= up[dep], phi *= up[dep] - 1; dfs(dep + 1, d, phi); for(int i = 2; i <= ps[dep]; ++ i) d *= up[dep], phi *= up[dep], dfs(dep + 1, d, phi); }
signed main() {
int i, j, T; init(maxn - 5);
r1(T); while(T --) { r1(n, A); if(n % mod0 == 0) mod = mod1, pd = 1; else mod = mod0, pd = 0; Solvem(); pre(n); ans = 0; dfs(1, 1, 1); if(pd == 0) ans = Mul(ans, ksm(n, mod - 2)); else ans = Mul(ans / mod0, ksm(n / mod0, mod0 - 2)) % mod0; ans = (ans + mod0) % mod0; printf("%lld\n", ans); } return 0; }
}
signed main() { return Legendgod::main(), 0; }
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