There is another way of approaching this (you have to think in terms of factorizing 486 = 2*35 and 1944 = 2335 for this):
Let a = logn(486√2) ...(1)
Then it's also true that a = log2n(1944) ...(2)
It's useful to write (1) as a = logn(2*35√2) = logn(3523/2) so that na = 3523/2 ...(3)
Similarly, with (2) we have a = log2n(2335) so that (2n)a = 2335 or 2ana = 2335 ...(4)
Substituting from (3) into (4) we get 2a3523/2 = 2335 from which 2a = 23/2 so that a = 3/2.
Putting this back into (3) we have n3/2 = 3523/2 so n = (3523/2)2/3 or
n = 2(35)2/3 = 2*310/3 = 2*(3931)1/3
n = 2*33*31/3
Finally: n = 54*31/3