Hmm, strange, when I run this:
$ sha256sum Solus-4.1-Budgie.iso.sha256sum
I get this: 10fdac7f8ed6fd951927024d642099ddce25160c52d48c6cef927266788a9398 Solus-4.1-Budgie.iso.sha256sum
But when I open this file like you said and look into it there is this: 4bf00f2f50e7024a71058c50c24a5706f9c18f618c013b8a819db33482577d17 Solus-4.1-Budgie.iso
Sha256sum the iso directly in a terminal I get this:
$ sha256sum Solus-4.1-Budgie.iso
4bf00f2f50e7024a71058c50c24a5706f9c18f618c013b8a819db33482577d17 Solus-4.1-Budgie.iso
(I removed the iso from its folder.)