select distinct acct 
from tbl_CYProcessedSales
where ISNUMERIC(Acct) > 0
order by acct

--===== Return all characters that ISNUMERIC thinks is numeric
     -- (uses values 0-255 from the undocumented spt_Values table
     -- instead of a loop from 0-255)
 SELECT [Ascii Code] = STR(Number),
        [Ascii Character] = CHAR(Number),
        [ISNUMERIC Returns] = ISNUMERIC(CHAR(Number))
   FROM Master.dbo.spt_Values
  WHERE Name IS NULL
    AND ISNUMERIC(CHAR(Number)) = 1

Ascii Code Ascii Character ISNUMERIC Returns 
---------- --------------- ----------------- 
         9 	               1
        10 
               1
        11 
               1
        12                1
        13 
               1
        36 $               1
        43 +               1
        44 ,               1
        45 -               1
        46 .               1
        48 0               1
        49 1               1
        50 2               1
        51 3               1
        52 4               1
        53 5               1
        54 6               1
        55 7               1
        56 8               1
        57 9               1
       128 €               1
       160                 1
       163 £               1
       164 ¤               1
       165 ¥               1

 SELECT *
   FROM sometable
  WHERE somecolumn NOT LIKE '%[^0-9]%'

 CREATE FUNCTION dbo.IsAllDigits 
/********************************************************************
 Purpose:
 This function will return a 1 if the string parameter contains only 
 numeric digits and will return a 0 in all other cases.

 --Jeff Moden
********************************************************************/
--===== Declare the I/O parameters
        (@MyString VARCHAR(8000))
RETURNS INT
     AS
  BEGIN
         RETURN (SELECT CASE 
                          WHEN @MyString NOT LIKE '%[^0-9]%'
                          THEN 1
                          ELSE 0
                        END)
    END

SELECT DISTINCT acct
FROM tbl_CYProcessedSales 
WHERE patindex('%[~`!@#$%^&*()_=+\|{};",<>/?a-z]%',acct)=0
ORDER BY acct