It depends on the city.
05 is the post code of Mandalay Division, Myanmar. As it has different townships, each township has different individual code. For example, Chan Aye Thar San Township of Mandalay is 05072.
The country code and area code of Aungban, Myanmar is 95, (0)81.
The country code and area code of Aunglan, Myanmar is 95, (0)69.
The country code and area code of Bagan, Myanmar is 95, (0)61.
The country code and area code of Bago, Myanmar is 95, (0)52.
The country code and area code of Dawei, Myanmar is 95, (0)59.
The country code and area code of Hakha, Myanmar is 95, (0)70.
The country code and area code of Hinthada, Myanmar is 95, (0)44.
The country code and area code of Hpa-an, Myanmar is 95, (0)58.
The country code and area code of Kale, Myanmar is 95, (0)73.
The country code and area code of Kyaington, Myanmar is 95, (0)84.
The country code and area code of Kyaukse, Myanmar is 95, (0)66.