10+9+9+9+9+99+9+9+9+9+9+9++9+99+9+9+99+99+9+9+9+99+99+9+99+9+9+9+9+9+99+99*123123143*123154346457568578*123434654675678*34254534
+1090 Just use the site calculator.
Or look below.
$${\mathtt{10}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{99}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{99}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{99}}{\mathtt{\,\small\textbf+\,}}{\mathtt{99}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{99}}{\mathtt{\,\small\textbf+\,}}{\mathtt{99}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{99}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{99}}{\mathtt{\,\small\textbf+\,}}{\mathtt{99}}{\mathtt{\,\times\,}}{\mathtt{123\,123\,143}}{\mathtt{\,\times\,}}{\mathtt{123\,154\,346\,457\,568\,578}}{\mathtt{\,\times\,}}{\mathtt{123\,434\,654\,675\,678}}{\mathtt{\,\times\,}}{\mathtt{34\,254\,534}} = {\mathtt{6\,347\,165\,199\,165\,034\,771\,606\,389\,461\,286\,355\,523\,177\,410\,471\,792}}$$
It might be easier to look here, since the answer probably isn't visible.
