[xsl] last two characters

[ram <ram_kurra@xxxxxxxxxxx>]

Hi,
  I have an xml which contains 

<Number>12345678912345678501234</Number>
I want to remove last two characters of this string and store it in variable
and also i need last two characters which i have stripped off.

<xsl:template
match="/">
	<xsl:variable name="s" select="/Number" />
	<xsl:value-of
select="substring($s, 1, string-length($s) - 2)" />
 </xsl:template>
This template removes last two characters and gives me 123456789123456785012.
I need 34 in another variable.is there any function something like last(xxx)
available .