Problem
NT-B1-M01-P004 Divisors of 840
#4
★☆☆☆☆ Level 1 of 5
Find the number of positive divisors of \(840\).
First factorise the number into prime powers.
\(840=84\cdot10=(2^2\cdot3\cdot7)(2\cdot5)=2^3\cdot3\cdot5\cdot7\). Hence the number of divisors is \((3+1)(1+1)(1+1)(1+1)=32\).
Emphasizes choosing each exponent from \(0\) to its maximum.