\(66 = 2.3.11\)
\(785 = 5.157\)
\(782 = 2.17.23\)
\(510 = 2.3.5.17\)
\(210 = 2.3.5.7\)
\(222 = 2.3.37\)
\(321 = 3.107\)
\(261 = 3^2 . 29\)
số 66 gồm 8 ước :1;2;3;6;11;22;33;66 số 101 gồm 2 ước:1;101
\(Ư\left(66\right)=\left\{1;2;3;6;66\right\}\)
\(Ư\left(101\right)=\left\{1;101\right\}\)
\(Ư\left(210\right)=\left\{1;2;3;5;6;7;10;21;210\right\}\)
\(Ư\left(321\right)=\left\{1;3;321\right\}\)
\(Ư\left(261\right)=\left\{1;3;9;261\right\}\)
\(Ư\left(785\right)=\left\{1;5;785\right\}\)
\(Ư\left(782\right)=\left\{1;2;17;23;46;34\right\}\)
\(Ư\left(761\right)=\left\{1;761\right\}\)
\(Ư\left(222\right)=\left\{1;2;3;6;74;37;111;222\right\}\)
\(Ư\left(510\right)=\left\{1;2;3;5;6;10;74;85;102;510\right\}\)
1: \(66=2\cdot3\cdot11\)
=>Có (1+1)*(1+1)*(1+1)=8(ước)
2: \(101=101\)
=>Có 2 ước
3: \(210=2\cdot3\cdot5\cdot7\)
=>Có (1+1)*(1+1)*(1+1)*(1+1)=16(ước)
4: \(321=3\cdot107\)
=>Có (1+1)*(1+1)=4 ước
5: \(261=3^2\cdot29\)
=>Có (1+1)*(2+1)=3*2=6 ước
6: \(785=5\cdot157\)
=>Có (1+1)*(1+1)=4 ước