To convert gigameters (Gm) to millimeters (mm), you need to multiply the value in gigameters by 999999999999.
So, to convert 1.4e-9 Gm to mm: 1.4e-9 Gm * 999999999999 = 1400 mm
Therefore, 1.4e-9 gigameters is equal to 1400 millimeters.
This below table contains list of length units and conversion values:
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