Réponse:

261954÷2=130977

130977÷3=43659

43659÷3=14553

14553÷3=4851

4851÷3=1617

1617÷3=539

539÷7=77

77÷7=11

donc 2×3×3×3×3×3×7×7×11=261954

261954 ÷ 2 = 130977

130977 ÷ 3 = 43659

43659 ÷ 3 = 14553

14553 ÷ 3 = 4851

4851 ÷  3 = 1617

1617 ÷ 3 = 539

539 ÷ 7 = 77

77 ÷ 7 = 11

Donc 261954 = 2 x 3 x 3 x 3 x 3 x 3 x 7 x 7 x 11

                       = 2 x 3⁵ x 7² x 11