MOD = 10**9 + 7

dp = [0] * 27
s = input()
dp[26] = 1
ans = 0
for z, c in enumerate(s):
    x = ord(c) - ord('a')
    ndp = [0] * 27
    for i in range(27):
        if i == x:
            ndp[x] = (ndp[x] + dp[i] * 2) % MOD
        else:
            ndp[x] = (ndp[x] + dp[i]) % MOD
            ndp[i] = (ndp[i] + dp[i]) % MOD
            ans += dp[i] * pow(2, len(s)-1-z, MOD)
            ans %= MOD
    dp = ndp
    #print(dp)
    #print(ans)
print(ans)