micropython maths lib?

We've run into trouble with a lineofbestfit equation on the gpy. Regular python gives y=999.97 for x=420
>>> x=420 >>> 236123330.633392+3683284.06273057*x+23906.7876866458*x**2+82.646351259391*x**3+0.160502156282077*x**4+0.000166027946373191*x**5+0.0000000714703479619462*x**6 999.9718719124794
but the gpy returns 352
>>> x=420 >>> 236123330.633392+3683284.06273057*x+23906.7876866458*x**2+82.646351259391*x**3+0.160502156282077*x**4+0.000166027946373191*x**5+0.0000000714703479619462*x**6 352.0
Wondering if anybody knows a good maths package for micropython or some other workaround?