Can't bind to 'startingCategory' since it isn't a known property of 'div'

I am stuck with Angular 6 code telling me "Can't bind to 'startingCategory' since it isn't a known property of 'div'." I am still fairly new to Angular, so please be kind :)

I'm trying to just read properties from my typescript and display them as properties within a div.

/document.component.ts

import { Component, OnInit } from '@angular/core';

@Component({
    selector: 'app-document',
    templateUrl: './document.component.html',
    styleUrls: ['./document.component.css']
})
export class DocumentComponent implements OnInit {
    title: string = "Documents";
    startingCategory: number = 0;
    orgId: number = 0;
    isAdmin: boolean = false;

    constructor() { }

    ngOnInit() {
    }
}

/document.component.html

<div id="DocumentManager" 
    data-title="{{title}}" 
    data-startingCategory="{{startingCategory}}" 
    data-orgId="{{orgId}}" 
    data-isAdmin="{{isAdmin}}">
</div>