Hacked? I work in a hotel. In the call log 4 extensions on the same day dialed phone numbers.?

These numbers dialed were 1603978999, 16039999999, 1603866451, and 1603470. The first 2 numbers were dialed at 18:37 and 18:38 and ran all night. the other 2 numbers were both dialed at 11:58 and ran all night. 3 of these 4 numbers arent even complete phone numbers. It also seems they are NH area codes. Lasthy, the extensions do not exsist within the hotel. They are not a guest room or office. Someone would have had to tap into the phone system right?