Html encode in PHP

I searched for hours, and I tried almost everything suggested.
This worked for almost every entity :

$input = "āžšķūņrūķīš ○ àéò ∀∂∋ ©€ ♣♦ ↠ ↔↛ ↙ ℜ℞";


echo htmlentities($input, ENT_HTML5  , 'UTF-8');

result :

āžšķūņrūķīš ○ àéò ∀∂∋ ©€ ♣♦ ↠ ↔↛ ↙ ℜ℞rx;