[17th Miss Regt]

Mass. IIRC the radius (event horizon) of a black hole is a linear function of its mass. The radius of a black hole this massive would be about 30 billion kilometers. The solar system would fit quite comfortably inside this volume.

[SunTzuWu]

Mass. IIRC the radius (event horizon) of a black hole is a linear function of its mass. The radius of a black hole this massive would be about 30 billion kilometers.

You are correct in saying that black holes are measured by their mass not their volume. Black holes can have a measurable circumference but the radius, (and therefore the diameter) is infinite.