def _str_conv(number, rounded=False):
    """
    Convenience tool to convert a number, either float or int into a string.

    If the int or float is None, returns empty string.

    >>> print(_str_conv(12.3))
    12.3
    >>> print(_str_conv(12.34546, rounded=1))
    12.3
    >>> print(_str_conv(None))
    <BLANKLINE>
    >>> print(_str_conv(1123040))
    11.2e5
    """
    if not number:
        return str(' ')
    if not rounded and isinstance(number, (float, int)):
        if number < 100000:
            string = str(number)
        else:
            exponant = int('{0:.2E}'.format(number).split('E+')[-1]) - 1
            divisor = 10 ** exponant
            string = '{0:.1f}'.format(number / divisor) + 'e' + str(exponant)
    elif rounded == 2 and isinstance(number, (float, int)):
        if number < 100000:
            string = '{0:.2f}'.format(number)
        else:
            exponant = int('{0:.2E}'.format(number).split('E+')[-1]) - 1
            divisor = 10 ** exponant
            string = '{0:.2f}'.format(number / divisor) + 'e' + str(exponant)
    elif rounded == 1 and isinstance(number, (float, int)):
        if number < 100000:
            string = '{0:.1f}'.format(number)
        else:
            exponant = int('{0:.2E}'.format(number).split('E+')[-1]) - 1
            divisor = 10 ** exponant
            string = '{0:.1f}'.format(number / divisor) + 'e' + str(exponant)
    else:
        return str(number)
    return string