What MySQL will return on adding microseconds in the timestamp value for converting it into an integer?

As we know that the value of timestamp can be converted to a number of seconds with the help of UNIX_TIMESTAMP() function. MySQL would ignore the microseconds added to the value of timestamp because the value of UNIX_TIMESTAMP is only 10digits long.

Example

mysql> SELECT UNIX_TIMESTAMP('2017-10-22 04:05:36')AS 'Total Number of Seconds';
+-------------------------+
| Total Number of Seconds |
+-------------------------+
| 1508625336              |
+-------------------------+
1 row in set (0.00 sec)

mysql> SELECT UNIX_TIMESTAMP('2017-10-22 04:05:36.200000')AS 'Total Number of Seconds';
+-------------------------+
| Total Number of Seconds |
+-------------------------+
| 1508625336              |
+-------------------------+
1 row in set (0.00 sec)

The queries above shows that the output remains same even after adding the 6 digits value of microseconds.