I'm encountering an error when evaluating units with a power sign (squared units) with BigNumber on.

Example:

const math = require('./math.min.js')
math.config({number: 'BigNumber', precision: 64}) //disable big number and the following expression works fine, but with big number on, it fails
math.eval('9.7 meters^2')

The error is:

TypeError: Unexpected type of argument in function pow (expected: number or string or boolean, actual: BigNumber, index: 1)