Ok .......sorry to all you big brothers....I was eager to learn, but I forgot to mention that I was trying and will keep trying so that I will be helping others as you are doing now.

Ok here is what I have done for prime numbers and palindromes, If I have made any mistakes in them please do tell me.

-------------PRIME NUMBERS---------

declare
v_cont number :=2;
v_prime number :=&Num;
begin
for v_cont in 2..200
loop
if v_prime > 200 then
dbms_output.put_line('Number too Large');
exit;
elsif
v_prime <= 0 then
dbms_output.put_line('Number too Small');
exit;
elsif
mod(v_prime, v_cont) = 0 then
dbms_output.put_line('Number ' ||v_prime|| ' is not a Prime number');
exit;
elsif v_cont = v_prime-1 then
dbms_output.put_line('Number ' ||v_prime|| ' is a Prime number');
end if;
exit when v_cont=v_prime-1;
end loop;
end;
/

------------PALINDROME-------
Declare
word VARCHAR2 (100):='&word';
i number;
j number;
BEGIN
j:=LENGTH(word);
FOR i IN 1..j
LOOP
IF SUBSTR(word,i,1) != SUBSTR(word,j-i+1,1) THEN
dbms_output.put_line(word|| ' is not a Palindrome');
exit;
else
dbms_output.put_line(word|| ' is a Palindrome');
exit;
END IF;
END LOOP;
END;
/