mod = 1000000007
eps = 10**-9


def main():
    import sys
    input = sys.stdin.readline

    S = input().rstrip('\n')
    N = len(S)

    pow2 = [pow(2, i, mod) for i in range(N+1)]
    dp = [[0] * 27 for _ in range(N+1)]
    dp[0][26] = 1
    for i, s in enumerate(S):
        for j in range(27):
            dp[i+1][j] = dp[i][j]
        js = ord(s) - 97
        dp[i+1][js] = (dp[i+1][js] + pow2[i])%mod

    ans = 0
    for i, s in enumerate(S):
        ans = (ans + ((pow2[i] - dp[i][ord(s) - 97])%mod * pow2[N - i - 1])%mod)%mod
    print(ans)


if __name__ == '__main__':
    main()