how the nucleus stability varies with the property of magic number?

The magic numbers are:

• proton: 2, 8, 20, 28, 50, 82, 114
• neutron: 2, 8, 20, 28, 50, 82, 126, 184
  these above things are only stable .. 

  Here is a simple chart that can help you decide is an element is likely stable.

• Calculate the total number of nucleons (protons and neutrons) in the nuclide
  • If the number of nucleons is even, there is a good chance it is stable.
• Are there a magic number of protons or neutrons?
  • 2,8,20,28,50,82,114 (protons), 126 (neutrons), 184 (neutrons) are particularly stable in nuclei.
• Calculate the N/Z ratio.
  • Use the belt of stability figure to determine the best way to get from an unstable nucleus to a stable nucleus..
    BY THE ABOVE METHOD ALSO U CAN CALCULATE STABILITY .. 
    Also, there is the concept that isotopes consisting a combination of even-even, even-odd, odd-even, and odd-odd are all stable. There are more nuclides that have a combination of even-even than odd-odd. Just like there exist violations to the octet rule, many isotopes with no magic numbers of nucleons are stable.
    HOPE IT CLEARS YOUR DOUBT 
    IF NOT UNDERSTOOD THEN LET ME KNOW .. 
    ALL THE BEST ..