x = 1111111234.6547389758965789345
y = formatC(x, digits = 8, format = "f")
# [1] "1111111234.65473890"
https://www.r-bloggers.com/number-formatting/
https://stackoverflow.com/questions/3443687/formatting-decimal-places-in-r
https://stat.ethz.ch/R-manual/R-devel/library/base/html/formatc.html