As'salamu Alaikum dear brother Mohamed,
I am not sure what the number 144,000 means. To me,
it is a mystery. It may not be a literal number.
And no, it is not referring to the number of Jews
who were with Prophet Muhammad, peace be upon him,
during his time. It could refer to future ones that
will embrace his Message, Islam, during a certain
period. I am not sure.