mb_chr
PHP 7 >= 7.2.0, PHP 8
mb_chr - Return character by Unicode code point value
Example #1 Testing different code points
Result: string(1) "A"
string(1) "A"
string(1) "?"
string(1) "?"
string(3) "€"
bool(false)
string(4) "🐘"
bool(false)
Example #2 of mb_chr