What is the formula for finding 13^123

$${{\mathtt{13}}}^{{\mathtt{123}}} = {\mathtt{103\,521\,923\,711\,427\,330\,139\,508\,660\,561\,111\,399\,310\,356\,231\,562\,909\,825\,053\,544\,787\,423\,528\,887\,795\,603\,512\,927\,942\,762\,680\,653\,876\,132\,399\,975\,884\,814\,583\,882\,073\,552\,996\,857\,463\,797}}$$