JSFiddle - React, Tailwind, and code Playground
JavaScript
//ATTEMPT 1
/*ungolfed
n=prompt(r=0);
for(j=n-2;j++<=n;)
{
p=1;
for(i=2;i<j;i++)
if(j%i==0)
p=0;
r|=p;
}
alert(r);
*/
//golfed
n=prompt(r=0);for(j=n-2;p=j++<=n;r|=p)for(i=1;++i<j;)p=j%i?p:0;alert(r)