302-356-0543 Weird Phone calls From Delaware

I have been receiving this weird phone calls from Delaware number 303-356-0543. I have been ignoring it but today I answered it several times because I thought maybe its a friend who want to great merry Christmas but no one answered. They hold on in a little bit and hang up. My question is how did this person got my number. Who are this individuals? When I look up in the internet, there's a lot of complaint about this number. Yes Its from Delaware. Its a land line number issued by Paetec communications, inc. Folks beware of this number. If they want to talk to us they should answer or leave a voice mail. Just beware!