650 + 290 = 940
94
The estimate for the product of 289 and 7 is 2,000.
578
1 x 289 = 289
1, 17 and 289.
171,578
289 = 17 x 17
The prime factors of 289 are 17 and 17 (i.e. 289 = 17*17).
The prime number (factor) of 289 is: 17
17*17 = 289
137 plus 149 plus 162 plus 201 plus 217 plus 289 plus 372 = 1,527
289 - 256 = 33