1,2,13,27,41,56,63,67,68,70,72,79,80合數:質數:奇數:偶數:

1,2,13,27,41,56,63,67,68,70,72,79,80合數:質數:奇數:偶數:


合數:27,56,63,68,70,72,80
質數:2,12,41,67,79
奇數:1,13,27,41,63,67,79
偶數:2,56,68,70,72,80



How many digits does the product 2516(25的16次方)*238(2的38次方)have?


25^16*2^38=2^6*(25*2*2)^16=64*100^16;
所以是16*2+2=34比特