src/lib/IBAN.php
public function getBankAccountNumber()
    {
        $countryCode = $this->getCountryCode();
        $length = static::$ibanFormatMap[$countryCode][0] - static::INSTITUTE_IDENTIFICATION_LENGTH;
        return substr($this->iban, static::BANK_ACCOUNT_NUMBER_OFFSET, $length);
    }
public function getBankAccountNumber()
    {
        $countryCode = $this->getCountryCode();
        $length = static::$ibanFormatMap[$countryCode][0] - static::INSTITUTE_IDENTIFICATION_LENGTH;
        return substr($this->iban, static::BANK_ACCOUNT_NUMBER_OFFSET, $length);
    }
public function getBankAccountNumber ( ) { $ countryCode = $ this -> getCountryCode ( ) ; $ length = static :: $ ibanFormatMap [ $ countryCode ] [ 0 ] - static :: INSTITUTE_IDENTIFICATION_LENGTH ; return substr ( $ this -> iban , static :: BANK_ACCOUNT_NUMBER_OFFSET , $ length ) ; }
Extract Bank Account number from IBAN

@return string
Extract Bank Account number from IBAN