Find the smallest positive integer N such that 


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&#x00A0;<i>N</i>
<div class="hrcomp"><hr noshade="noshade" size="1"/>2<br /></td><td nowrap="nowrap" align="center">
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      is a perfect cube, 


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&#x00A0;<i>N</i>
<div class="hrcomp"><hr noshade="noshade" size="1"/>3<br /></td><td nowrap="nowrap" align="center">
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      is a perfect fifth power and 


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&#x00A0;<i>N</i>
<div class="hrcomp"><hr noshade="noshade" size="1"/>5<br /></td><td nowrap="nowrap" align="center">
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      is a perfect seventh power.