Udayapur District and in 2001 had a population of 287,689, in 2011 of 317,532, in 2021 of 342,773 The district border of Udayapur is drawn by Natural border with rivers and hills.
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Nepal officially the Federal Democratic Republic of Nepal is a landlocked country in South Asia located mainly in the Himalayas but also includes parts of the Indo-Gangetic Plain. With an estimated population of 26.4 million, it is 48th largest country by population and 93rd largest country by area. It borders China in the north and India in the south, east, and west while Bangladesh is located within only 27 km (17 mi) of its southeastern tip and Bhutan is separated from it by the Indian state of Sikkim.

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