St. Peter (30 to 64/67 AD): 34 or 37 years, of which, according to tradition, he spent 25 in Rome. (Peter was not however known as pope in his lifetime)
... symbol
<math>\pm \sqrt {b^2-4ac}</math>
in the formula should be understood as "either of those element(s) of the field whose square equals b2 - 4ac". ...