I think your question is not complete. WHich links are you asking for, Outgoing links or in-bound links on your site ? As there is a vast difference and certain value for these type of links, so please be specific.
keep it looking 'natural'. You have visited web pages, you know what a 'normal' page looks like. It doesn't contain 20,000 outgoing links. There is also a school of thought that you should keep your page size below 100kb for the sake of the engines, and that limits how many links you could have on there anyway.
There is nothing like limitation for you as that website is yours and have full access for you to keep links as much as you want. But if you are asking in terms of SEO then don't let go much outbound links and create clean no. of internal links from your pages but don't stuff. There is no exact amount declared ever but use your brain to decide how much amount of links will not irritate users and won't look spam to BOTs.
No there is no limitation but in few articles I have read that the page should not contain more than 100 links...
There are no limits for giving links in a page as long as they don't affect the beauty of your web page.
Take a look at any ol Wikipedia article, and you'll see HUNDREDS of links per page...BUT, almost all of them are links to pages within it's own site. Some people forget about the power of internal linking for ON Page SEO. But, common sense is also needed. Don't create a link out of some stupid text like "and then I was going". Use keywords to create a link to another page on your site that really IS about what the keywords say it is. Example: If you have a site about "Red-Bananas". Let's say you have a page on "Red-Banana-Recipes". Well, you could say ...Now that you're learned about growing red bananas, let's talk about some great recipes. and make that link(growing red bananas) link to your "growing-red-bananas" page. Just stay focused with your keywords and make sure you point them to correct locations. Also, sidenote here, your main keyword on each page, bold it a couple times, italics it a couple times, underline it here and there. Whatever it takes, just put a lil extra emphasis on it.
There's no set figure for the number of links on the page. But that doesn't mean that you have hundreds of unnecessary links on the webpage. Ideally, for maintaining quality of the webpage, there should be no more than 25 out-bound links on any page. It'll pass all the link juice and the PR to all the sites that have out-bound links on that page.
Google does deal with pages over 100k. It's just that first 100k is cached. The original Google white paper describes how the first character has the most weight and has you add characters their importance reduces. When you get to a certain limit each addition character only has a minimum of importance. In this original paper we never got to a point where additional characters did not count. The 100 link limit has been in the guidelines for a long period of time. Google updated their guidelines at about the same time as they launched their sitemap XML program. At that time the 100 link limit was repeated. In fact, it's the only point which Google mentions twice.