You can use Spannable to achieve this, its more flexible in case you need to put this only in a part of the text. Here is an example:
textview.setText("29,500", TextView.BufferType.SPANNABLE);
final StrikethroughSpan STRIKE_THROUGH_SPAN = new StrikethroughSpan();
Spannable spannable = (Spannable) textview.getText();
spannable.setSpan(STRIKE_THROUGH_SPAN, 0, textview.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
textview.setText(spannable);