The K898-005 is a Kenda model code that no fitting information can be gleaned from directly. The 54-559 (you wrote 359) is the ISO measurement. The first number (54) is the approximate outside width of the inflated tire in millimeters, approximate because it varies slightly depending on the rim width it's mounted on. The second number is the diameter of the circle formed by the tire bead, which corresponds to the bead seat of the rim. 559 is the most common of the 26" sizes, sometimes known as "mountain bike 26 inch" and similar names. It's probably the actual most common size in the world, but there are a couple of other 26" sizes, and when getting 26" road tires it can be easy to accidentally get one of those instead because they're more commonly associated with thin tires. So don't buy a tire that says 571, 584, 590, or 597. You want it to say 559. Most but not all tires for 559 are going to have their width described with a decimal rather than a fraction (26x1.125 rather than 26x1-1/8 for example). Most but not all currently produced tires have an ISO number hiding somewhere on them, so you're looking for something that says xx-559, where xx is width.
As for the minimum width, for practical purposes you want something that ideally has 2-3mm overhang past the rim and is under no circumstances narrower than the rim. So 26x1.25 (32-559) is the start of the reasonable widths, 26x1.125 (28-559) is pushing it, and 26x1 (25-559) will more or less physically work but is kind of asking for trouble.