How to use python to insert a date formatted as a bigint datatype in MySQL DB?

I tried to use timestamp to forge a 14 digits int in form of YYYYMMDDHHMMSS in MySQL DB as primary key for later indexing. While 14 digits integer in MySQL is too large for int datatype, so I created table in bigint datatype. I have converted the timestamp into int with my python codes, but while I connected to MySQL, then trying insert 14 digits int into tables with bigint tables. It seems not working. And I queried tables with previous inserted rows for testing, it returns 20771213011177L. With a L in the end. So I noticed it might be the datatypes causing the issue. I try to convert the int into long, but the failure is still there. Is there a way I can insert 14 digits INT into MySQL DB with BIGINT datatype or I have to convert it into some other way? By the way, I'm using python 2.

The table was created this way:

CREATE TABLE IF NOT EXISTS table_1 (
   table_primary_key BIGINT(14) PRIMARY KEY, 
   value1 DOUBLE,
   value2 DOUBLE,
   event_date_time DATE
);

Then here are codes:

from __future__ import print_function
from collections import OrderedDict
import serial, struct, sys, time, json, subprocess
import datetime
import mysql.connector

mydb = mysql.connector.connect(
    host = "localhost",
    user = "admin",
    password = "S2Bgz4AnVWLQQVun",
    db = "testdb"
)

mycursor = mydb.cursor()

JSON_FILE = '/home/yser/proofvalues.json'

...


if __name__ == "__main__":
    currentDateTime = datetime.datetime.now()
    primaryKey = int(currentDateTime.strftime("%Y%m%d%H%M%S"))
    primaryKey_long = long(primaryKey)

..
# sensor reads and process out with two working variables
..


# This json is for proof values.
try:
        with open(JSON_FILE) as json_data:
            data = json.load(json_data)
    except IOError as e:
        data = []

    # check if length is more than 1000 and delete first element
    if len(data) > 1000:
        data.pop(0)

    # append new values
    jsonrow = {'table_primary_key': primaryKey,'value1': values[0], 'value2': values[1], 'event_date_time': currentDateTime.strftime("%Y-%m-%d %H:%M:%S")}
    data.append(jsonrow)


try:
        mycursor.execute("INSERT INTO table_1(table_primary_key, value1, value2, event_date_time) VALUES (%s, %s, %s, %s)",(primaryKey, values[0], values[1], currentDateTime.strftime("%Y-%m-%d %H:%M:%S")))
        mydb.commit()
except:
        mydb.rollback()

sys.exit()