MOD = 10 ** 9 + 7
N,K = map(int,input().split())
fact = [1]*(N+1)
rfact = [1]*(N+1)
r = 1
for i in range(1, N+1):
    fact[i] = r = r * i % MOD
rfact[N] = r = pow(fact[N], -1, MOD)
for i in range(N, 0, -1):
    rfact[i-1] = r = r * i % MOD

# nCk (mod MOD) を求める
def comb(n, k):
    return fact[n] * rfact[k] * rfact[n-k] % MOD

KN = pow(K,N,MOD)
avg = ((K * (K + 1) // 2) * pow(K,-1,MOD)) % MOD
ans = 0
TKN = KN
for i in range(N):
    ans += TKN * comb(N,i)
    ans %= MOD
    TKN = (TKN * avg) % MOD
print(ans)