### Lastly - Well

What are the last two digits of 2^(2^2003)?

### Counting Factors

Is there an efficient way to work out how many factors a large number has?

### Summing Consecutive Numbers

15 = 7 + 8 and 10 = 1 + 2 + 3 + 4. Can you say which numbers can be expressed as the sum of two or more consecutive integers?

$32 \times 46 = 1472$
$23 \times 64 = 1472$