DECLARE
    n number(3);
    s number(3):=0;
    t number(3);
  BEGIN
    n:=&n;
    t:=n;
        while t>0 loop
          s:=s+power((t mod 10),3);
          t:=trunc(t/10);
        end loop;

        if(s=n) then
          dbms_output.put_line('The Given Number ' || n || ' is an Armstrong Number');
        else
          dbms_output.put_line('The Given Number ' || n || ' is Not an Armstrong Number');
        end if;
  END;

 

 OUTPUT:

 NOTE: We used SQL Developer and Oracle XE to Execute this Program. 

The Given Number 153 is an Armstrong Number