It is: 1/3 times 1347 = 449
Black death affected Europe from about 1340 onwards. It killed large population of Europe, almost 100 million people died of this deadly disease. It reduced worlds population from 450 million to 350 million.
Neither one is prime.
369 +1347 = 1716
1, 3, 449, 1347.
1347
No-one died in London in 1347 in the Black Daeth, it wasn't introduced at the time it was only in Italy
2747
1347 + 5691 = 7038
3 x 449 = 1347
-1328
It is: 1347/3 = 449
around 20 million people died