Mono More Condition_symptoms Can I Power More Than 1 Sub On A Mono Amp?

Can I power more than 1 sub on a mono amp? - mono more condition_symptoms

400rms subwoofer with 4 in a room together they could work on a mono amp? If the amplifier 1000w would be this good or not?

Let's add each subgroup: 400x4RMS for 1600W?
This means that we need a mono-1600W?
Please let me know the mind confused.