Write a shell script to reverse a number given by a user. - OS

if [ $# -eq 1 ]
then
if [ $1 -gt 0 ]
then
num=$1
sumi=0
while [ $num -ne 0 ]
do
lnum=`expr $num % 10`
sumi=`expr $sumi \* 10 + $lnum`
num=`expr $num / 10`
done
echo "Reverse of digits is $sumi of $1"
else
echo " Number is less than 0"
fi
else
echo "Insert only one parameter "
fi