Question

2^32-1能被一个两位数整除,那这个两位数是?

Answer 1

2^32-1

=(2^16+1)(2^16-1)

=(2^16+1)(2^8+1)(2^8-1)

=(2^16+1)(2^8+1)(2^4+1)(2^4-1)

故这个两位数是2^4-1=15