If you have gross income of $4,050 or more in 2017 and are not a full time student under the age of 24 then no one can claim you as a dependent.
The 401(k) withdrawal would be entered as ordinary income and is only reported on your tax return, taxed at your current tax rate. If you were under the age of 59 1/2 or under the age of 55 and not separated from the company holding the retirement account then there will be a 10% early withdrawal penalty assessed on your tax return reported as a tax liability.
You will receive a Form 1099-R in January of the year following the withdrawal. The Form 1099-R is reported on your tax return.
