Convert byte value to MB in bash script

I have written a bash script to get the current Jjava heap memory size. I want to convert this value to MB. Below are the details

freememory=$((heapmax - heapused))
echo $freememory
Remaining Memory is : $freememory bytes"

If you want to convert to "human readable" units (like the -h switch used by utilities like df, du etc.) then try numfmt ex.

$ echo 123456789 | numfmt --to=iec
118M

$ echo 123456789 | numfmt --to=iec-i
118Mi

$ echo 123456789 | numfmt --to=si
124M

This is typically something you can use bc for.

echo "${freememory}/2^20" | bc

Attempting a single line of Python code to generate kilo to terra-byte values:

$ python -c "import sys;from math import *;a=float(sys.argv[1]);    \  
  m=int(round(log(a)/log(1000),3));                                 \
  print(a,'is',a/(pow(1000,m)),(' KMGT')[int(m)]+'B','free mem')"   \
  $(sed -nr 's/^.*MemFree:[ \t\n]+([0-9]+).*$/\1000/p' /proc/meminfo)

... actually, just append characters to KMGT to allow even larger quantities.

Lines:

1. launch python, import math and sys, get first arg into a
2. calculate the magnitude of a
3. print the result
4. create the first argument, what is to be in sys.argv[1]