1. A million millions.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• zillon,
• billoin,
• billibn,
• vilion,
• billionb,
• bullitn,
• bulliton,
• willin,
• billio,
• billons,
• biullion,
• milluion,
• biliion,
• pilion,
• milion,
• millon,
• billign,
• miillion,
• sirlion,
• billto

• billing,
• bullion,
• billow,
• Bouillion,
• balloon,
• million.

The adjective form of the word "billion" is "billionth".

The plural of the "billion" can be the "billions".

The singular of the "billion" can be the "billion".