Taco lovers, rejoice. National Taco Day is Sunday, and whether you prefer hard shell or soft, it's the perfect day to eat the tortilla-wrapped food. 

Last year, the United States consumed 4.5 billion tacos, according to the National Taco Day website. End-to-end, those tacos would span 490,000 miles, which could get you to the moon and back. Those same tacos would weigh about 770 million pounds, or about the same weight as 64,000 adult African elephants.

Typically tacos are filled with some sort of meat, like chicken, beef or fish, but there are also other varieties, such as the popular egg breakfast taco. You can top a taco with just about anything. Popular choices include chopped lettuce, tomato, onion, avocado and cilantro topped with dollops of sour cream. 

With the big taco holiday upon us, a number of restaurants are running deals to celebrate. Listed below are just some of the bargains. Be sure to check in with your favorite taco joint to see if they are running specials.

On the Border Mexican Grill and Cantina: The national chain is offering tacos for 50 cents each in honor of National Taco Day. â€œWe are always looking for a reason to be your favorite Mexican restaurant, so this is a complete natural for us,” said Ward Whitworth, president of On the Border, in a statement via Restaurant News.

Customers will be able to choose from either the beef, chicken or vegetable version of the restaurant's mini crispy tacos. On the Border anticipates selling 100,000 tacos Sunday. 

El Torito: The California chain is offering a free taco for any customer who says "secret taco" to their server, according to the National Taco Day website.

Margarita's Mexican Restaurant: The East Coast chain plans to celebrate National Taco Day with its Taco Gigante. Customers will be able to order the 2-pound, 12-inch behemoth throughout October.

Tijuana Flats: The restaurant chain with stores in Florida, Georgia, Indiana, South Carolina, North Carolina and Virginia is offering $2 tacos. Better yet, it's offering $1 draft beers to wash them down.

Fast food chain Taco Bell has not yet announced any deal for National Taco Day. But be sure to check out the hashtag #NationalTacoDay on Twitter throughout Sunday as companies announce deals.