29000000mL equals 29000L
K H D U D C M
Km Hm Dam m Dm Cm Mm
KL HL DaL L DL CL ML
Kg Hg Dag g Dg Cg Mg
Kilo Hacto Daca Deci Centi Milli
100 10 1 0 0.1 0.01 0.001
↑ here's the chart that can help you.
If that's hard to memorize, then use
' King Henry Died Unusually Drinking Chocolate Milk.'