A laserdisk-sized Blu-ray disk holds how much data?

A laserdisk's diameter is 30 cm, and diameter of the central hub roughly 10.6 cm.
Lets convert that to radius, so 15 cm radius total with a 5.3 cm radius for the central hub (where no information is recorded on).

Let's also assume that the outermost 2 mm aren't recorded on. The radius of a laserdisk becomes 14.8 cm, so Pi * 14.8^2 = 688.13 cm^2, minus the central hub radius of 5.3 cm, Pi * 5.3^2 = 88.25 cm^2, for a total recordable surface area of about 599.89 cm^2.

So...

A laserdisk has an (approximated) total recordable surface area of about 599.89 cm^2

1 inches = 2.54 cm

A laserdisk has an (approximated) total recordable surface area of about 236.177 in^2

According to Wikipedia https://en.wikipedia.org/wiki/Areal_density_%28computer_storage%29

Compact discs (CDs) have an areal density of about 0.90 Gbit/in^2,
DVD disks have an areal density of about 2.2 Gbit/in^2.
Single-layer HD DVD have an areal density of 7.5 Gbit/in^2
Blu-ray disks have an areal density of around 12.5 Gbit/in^2

Gbit = gigabit = 125 megabytes

Wikipedia does not specify if that blu-ray disk is 1 layer or 4 layer.
Working backwards to understand where they got that density estimate from,
I calculate the above density estimate is for a blu-ray disk whose capacity is somewhere between 3 and 4 layers.
So 12.5 Gbit/in^2 is pretty near maximum possible density for a blu-ray disk, a little less, so I am happy enough with this estimate to run with it.

So...

12.5 Gbit/in^2 * 236.177 in^2 = 2952.2125 Gbits = 369026.5625 megabytes or 369.02 gigabytes of information

Ergo...

Blu-ray encoded information the size of a laserdisk disk could hold approximately 369.02 GB of information on a single side.