Answer
The pressure in intergalactic space is $4.14\times 10^{-17}~Pa$
Work Step by Step
We can find the pressure in intergalactic space:
$PV = NkT$
$P = \frac{NkT}{V}$
$P = \frac{(1)(1.38\times 10^{-23}~J/K)(3~K)}{1.0\times 10^{-6}~m^3}$
$P = 4.14\times 10^{-17}~Pa$
The pressure in intergalactic space is $4.14\times 10^{-17}~Pa$.
