S = list(input())
N = len(S)
for i in range(N):
    S[i] = ord(S[i]) - ord("a")

mod = 10 ** 9 + 7
two = [1] * (N + 1)
for i in range(N):
    two[i + 1] = two[i] * 2
    two[i + 1] %= mod

L = [0] * 26
sm = 0
ans = pow(2, N, mod) - 1
for i, s in enumerate(S):
    now = sm - L[s]
    ans += now * two[N - 1 - i]
    ans %= mod
    L[s] += two[i]
    sm += two[i]
    sm %= mod

print(ans%mod)