If I roll a 6-sided die, 28 times, and get the same number 28 times in a row, is this really a 1 in 1 Septillion chance?
(1/6)28 = 1 / 6, 140, 943, 214, 000, 000, 000, 000 (approx)
= 1 in 6.14 x 1021 (approx)
However a septillion is 1 in 1024, so (1/6)28 misses a septillion by (about) a factor of 1,000.