The answer is about 1 meter.
40,075km is about the circumference of the world.
Multiply by 1000 to convert to meters, so 40,075,000 meters, Divide this by Pi to get about 12756268.6.
Add 6 the circumference.
40,075,006. Divide by Pi to get the diameter.
About 12756270.6.
The diameter is increased by about 2. However, we need the radius to find how much it's stretched out in ANY direction. The radius is half the diameter, half both of those numbers to find that it is 1 meter. (Which is also half of 2, so you can do it that way if you want).
Tada, math!
I'm a bit lazy, so I'm won't show the numbers after you divide them by 2, so here's an easy example: 4-2 = 2. Okay.
4/2 =2
2/2 =1
2-1 =1
Same principle applies with all numbers, including the two I was working with above.