I am the official currency of a nation that is home to the world's highest mountain and also the birthplace of Buddha. My value is linked to that of the Indian Rupee, and I am subdivided into 100 paisa. Which currency am I?

1. My nation's flag is the only non-rectangular national flag in the world.
2. I am used in a country known for its unique blend of Hinduism and Buddhism.
3. My central bank is called 'Rastra Bank'.
4. The mountains in my nation are a major tourist attraction.