Without using a calculator, find the largest prime divisor of 5^12 minus 2 times 10^6 plus 2^12.

HelpBot Jul 14, 2020

#1**+2 **

625 x 625 x 625 =244,140,625

244,140,625 - [2 x 1,000,000] =242,140,625

2^4 x 2^4 x 2^4 =16 x 16 x 16 =4,096

242,140,625 + 4,096 =242,144,721

242,144,721 = 7 x 7 x 9 x 9 x 13 x 13 x 19 x 19

The largest prime divisor = 19

Guest Jul 15, 2020