How to do number 16 and 17 on Number of the day

Number 17- make a two digit number using the digit in ones place

first and the tens place second.

eg. 43 from December 7

Number: 9834.765

Then find from the prime factors

43-1, 43

so 43 is the only prime factor

1 is not prime.

Number 16- Only look at the whole number

Then go through the divisibility rules.