Masses; tired, huddled or otherwise

There are thirty megacities, scaling down from Tokyo at the top to Tianjin at 10.6 million just squeezing in.
The other Japanese megacity is Osaka at fifteenth position with 16.8 million population.

There are five megacities in China, three in India and two in the United States.

Seventeen capitals are classed as megacities; actually I think I miscounted and its eighteen. Hey, if Wikipedia contributors can do it, so can I.

Megacities not mentioned or referenced in this discussion thusfar include Cairo (16.1 million), London (15.5 million), Buenos Aires (14.5 million), Bangkok (14.5 million), Istanbul (13.8 million), Lagos, (13.2 million)  Tehran (13.2 million), Rio de Janiero (12.9 million), Rhine-Ruhr (12.19 million), Shenzhen (11.7 million) and Paris (10.7 million).