The area code 646 covers both Manhattan and the Bronx within New York City. It’s widely used by businesses across various industries. Manhattan, in particular, boasts the highest concentration of corporate headquarters in the United States. Notable institutions like the New York Stock Exchange, major broadcast television networks, and Silicon Alley call this area home. Silicon Alley, a hub for information technology, attracted nearly $3.9 billion in investments during the first three quarters of 2014. This impressive investment can be attributed to the city’s strategic location near transatlantic fiber optic trunk lines and its reputation as a prominent communications center in North America.