DECLARE @Number INT = 123456789
;WITH getDigitsCTE AS (
SELECT
SlNo = 1
, Quotient = @Number / 10
,Remainder = @Number % 10
UNION ALL
SELECT
SlNo = SlNo + 1
,Quotient / 10
, Quotient % 10
FROM getDigitsCTE
WHERE Quotient > 0
)
SELECT
OriginalNumber=@Number
,ReveredNumber =
STUFF((SELECT '' +
dw.Remainder + ' '
FROM getDigitsCTE dw
ORDER BY dw.SlNo
FOR XML PATH('')),1,0,'')
/*
OriginalNumber ReveredNumber
123456789 987654321
*/