### Counting Factors

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

### Differences

Can you guarantee that, for any three numbers you choose, the product of their differences will always be an even number?

### Funny Factorisation

Using the digits 1 to 9, the number 4396 can be written as the product of two numbers. Can you find the factors?

# Number Families

##### Stage: 3 Challenge Level:

How many different sets of numbers with at least four members can you find in the numbers in this box?

For example, one set could be multiples of $4$ {$8, 36 ...$}, another could be odd numbers {$3, 13 ...$}.