431126 is ningyuan county's identity card. The first and second digits of the ID number represent provincial administrative regions. The third and fourth places represent prefecture-level administrative regions. Among them, 1-2 and 51-7 represent prefecture-level cities; 21-5 means regions, autonomous prefectures and leagues; 9 represents the county-level administrative unit directly under the provincial government; In the identity card of a municipality directly under the Central Government, 1 represents the municipal district and 2 represents the county.
the fifth and sixth places represent county-level administrative regions. 1-18 means municipal districts or regions, autonomous prefectures and county-level cities under the jurisdiction of the Union; 21-8 represents counties and flags; 81-99 represents the county-level administrative units directly under the provincial government.
The last digit of the ID card number is calculated by the number compilation unit according to a unified formula. If someone's tail number is -9, X will not appear, but if the tail number is 1, X will be used instead, because if 1 is used as the tail number, this person's ID card will become 19 digits, and the 19-digit number violates the national standard, and the computer application system in China does not recognize the 19-digit ID card number. X is 1 in Roman numerals. Replacing 1 with X can ensure that citizens' ID cards meet national standards.