Supported Versions: PHP 4, PHP 5, PHP 7, PHP 8
Exponential expression
<?php pow(mixed $num, mixed $exponent): int|float|object
<?php         $numberExponent = floor(log10($number));

        $displayExponent = $numberExponent - ($numberExponent % 3);

        $number /= pow(10, $displayExponent);



        return trim(sprintf('%s%s', static::format($number, $precision, $maxPrecision), $units[$displayExponent] ?? ''));

    }