Bonjour,

1)

28/2 = 14

14/2 = 7

Diviseurs:

1,2, 4, 7, 14,

1+2+4 +7 +14 = 28

2)

64/2 = 32

32/2 = 16

16/2 = 8

8/2 = 4

4/2 = 2

diviseurs

1, 2,4, 8, 16, 32,

1+2+4+8+16+32 = 63

Il manque 1

3)

Presque parfaits:

2 (2+1 = 3 )

4 (2+1=3)

5 (5+1) = 6

8 (4+2+1= 7)

16 (1+2+4+8= 15)