a)
3^2 × 5^4
(2 + 1) × (4 + 1) = 3 × 5 = 15 divizori
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b) 10^3 × 4^6 × 7^4 =
2^3 × 5^3 × 2^12 × 7^4 =
2^15 × 5^3 × 7^4
( 15 + 1) × ( 3 + 1) × ( 4 + 1) =
16 × 4 × 5 = 320 divizori
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c) 644 000 = 2^5 × 5^3 × 7 × 23
(5 + 1) × ( 3 + 1) × ( 1 + 1 ) × ( 1 + 1) =
6 × 4 × 2 × 2 = 96 divizori
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d) 1 245 000 = 2^3 × 3 × 5^4 × 83
( 3 + 1) × ( 1 + 1) × ( 4 + 1 ) × ( 1 + 1) =
4 × 2 × 5 × 2 = 80 divizori
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