This is the output I get with node examples/gdalinfo.js:

Upper Left   (-5721999.51, -2925751.47) ( 25d24'23.23"W,  51d24' 5.75"S)
Upper Right  (-5721770.19, -2925751.47) ( 25d24'23.23"W,  51d23'58.33"S)
Bottom Right (-5721770.19, -2926104.99) ( 25d24'33.56"W,  51d23'58.33"S)
Bottom Left  (-5721999.51, -2926104.99) ( 25d24'33.56"W,  51d24' 5.75"S)
Center       (-5721884.85, -2925928.23) ( 25d24'28.40"W,  51d24' 2.04"S)

The first numbers par is in the projected coordinates system, the second pair is in WGS84.

The example uses gdal.CoordinateTransformation and gdal.decToDMS to obtain this result.