0000898430-01-500179 424B3 1 20010418 NORTHROP GRUMMAN CORP /DE/ 0001133421 3812 954840775 DE 1231 424B3 33 333-54800 1605286 1840 CENTURY PK E C/O NORTHROP GRUMMAN CORP LOS ANGELES CA 90067 3105536262 1840 CENTURY PARK EAST C/O NORTHROP GRUMMAN CORP LOS ANGELES CA 90067 NNG INC 20010129 424B3 1 d424b3.txt FORM 424B3