The given number is 636157
Remember, ten thousand is written as 10000. It has 5 digits. Thus, the place value of ten thousand is the 5th digit from the last digit. By applying this definition to the given number, the ten thousand place value is 3. Since the digit to the right of 3 is grater than or equal to 5, we would round up 3 by 1.
Therefore, rounding to the nearest ten thousand, it becomes 640000