Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
What's the approximate number of HUs when there are more than 2 digits, and 6 levels?

### Inputs:
table_name: table, columns: ['Name', 'Level', 'Digits', 'Average size (square miles)', 'Number of HUs (approximate)', 'Example name', 'Example code (HUC)']

### Response:
SELECT COUNT Number of HUs (approximate) FROM table WHERE Digits > 2 AND Level = 6