A reverse split is not done that way.
If XYZ, Inc. has 7,000,000 shares outstanding (issued) and they do a 1 for 7 split, they will then have 1,000,000 outstanding shares. Every shareholder electronically "turns in" their shares and are issued the new post-split shares.
So if you had 1,000 shares before the split, the old shares are cancelled and in their place you get 142.85 shares.
On the market, if the shares of XYZ had been selling for $1 before the reverse split, the second the split happens, each new share of XYZ, Inc (made up of 7 old shares) will start trading at $7.00 per share.
The old shares are gone, cancelled and deleted. They have been exchanged for new shares, each worth 7 times the value of an old share.
In the specific case of Cumulus, they now have 29.31 million new shares: pre-split they had slightly less than 210 million old shares.