Fnding RPM of encoder using simplepollrotator example

[MrWns14]

hi, sorry if this is out of question, im new in coding and sorry for my bad english.
im trying to find RPM of my shaft using lpd3806(400ppr) encoder. im using the example of simplepollrotator.
i set an experiment where i rotate the shaft for 1min and get 2270 value in the serial monitor.

1. Can i know what is the 2270 value stand for? is it in pulse per second or baudrate or something else?

2.By any chance, do u know how? because im quite lost . there a formular i find where rpm=pulse*60second/ppr. but i dindt understand and not sure if the value 2270 stand for pulse.

again im really sorry if this is out of question because i cant find the answer online and im stuck and cannot proceed with the calculation.

Thank you very much sir! im really really appreciate if u could help me with my problem , thank you sir