Numpy array size different when saved to disk (compared to nbytes)
For others references, From numpy documentation:

numpy.ndarray.nbytes attribute
ndarray.nbytes Total bytes consumed by the elements of the array.
Notes
Does not include memory consumed by non-element attributes of the
array object.

So, the nbytes just considers elements of the array.
Is it possible that a flat numpy 1d array's size (nbytes) is 16568 (~16.5kb) but when saved to disk, has a size of >2 mbs? 
I am saving the array using numpy's numpy.save method. Dtype of array is 'O' (or object).
Also, how do I save that flat array to disk such that I get approx similar size to nbytes when saved on disk? Thanks