public function getIntegerPart()
    {
        if ('0' === $this->coefficient) {
            return $this->coefficient;
        }

        if (0 === $this->exponent) {
            return $this->coefficient;
        }

        if ($this->exponent >= strlen($this->coefficient)) {
            return '0';
        }

        return substr($this->coefficient, 0, -$this->exponent);
    }