String a = "3736186567876876578956958769675785435673453453653543654354365435675671119238118911893939591735";
int aScale = 45;
String b = "134432345432345748766876876723342238476237823787879183470";
int bScale = 70;
int precision = 75;
RoundingMode rm = RoundingMode.DOWN;
MathContext mc = new MathContext(precision, rm);
String c = "2.7792318551469036747477068339450205874992634417590178670822889E+62";
int resScale = -1;
BigDecimal aNumber = new BigDecimal(new BigInteger(a), aScale);
BigDecimal bNumber = new BigDecimal(new BigInteger(b), bScale);