Something

on *:text:!natworld*:#:{
  if ($nick isop $chan) || ($nick ishop $chan) {
    if ($2 isnum 1-138) {
      set %natworld $2
      msg $chan the nature world is now %natworld
    }
   else notice $nick put a number 1-138
  }
 else notice $nick you arent hop or op
}

on *:text:!world:#:{
  if (%natworld != $null) {
    notice $nick nat world is: %natworld $+ .
  }
 else notice $nick its not set.
}