Update Where Column IN(1, 2) With Parameter

The problem is with @NUMERY parameter
in code behind i set

Dim dr As GridViewRow
Dim numery As String
numery = ""

For Each dr In GridView1.Rows
Dim numeros As Label = dr.Cells(0).Controls(1)
numery += numeros.Text & ", "
Next

numery = numery.TrimEnd(", ")

SqlDataSource1.UpdateParameters("NUMERY").DefaultValue = numery
'so numery will look like this 123, 65465, 54616, 56465

Update command looks like this :
UpdateCommand="UPDATE slon SET mrowka = @MROWKA WHERE (NUMER IN (@NUMERY))"

<UpdateParameters>
<asp:Parameter Name="MROWKA" />
<asp:Parameter Name="NUMERY" />
</UpdateParameters>

And because of @numery i have err: Error converting data type nvarchar to numeric.
how should i post "123, 65465, 54616, 56465" as parameter for this query ?