What is the smallest number with exactly 14 divisors?
Many numbers can be expressed as the sum of two or more consecutive integers. For example, 15=7+8 and 10=1+2+3+4. Can you say which numbers can be expressed in this way?
Helen made the conjecture that "every multiple of six has more
factors than the two numbers either side of it". Is this conjecture
Consider all two digit numbers ($10$, $11$, . . . ,$99$). In
writing down all these numbers, which digits occur least often, and
which occur most often ?
What about three digit numbers, four digit numbers and so