Does US patent 663007 make the use of substance covered by it the property of the people of America?

A patent grants the owner the right to exclude others from making, using or selling whatever is covered by the claims in the patent. Of course, the enforceability of any patent is subject to payment of maintenance fees during its patent term. Any patent that has expired for failure to pay a maintenance fee or by virtue of full patent term expiration is dedicated to the public. The government, like any other patent owner, has the same rights to exclude others. The owner of a patent has the right to enforce its patent rights, but there is no obligation to do so. Finally, the covered inventions of government owned patents are not free for use by any American citizen simply by virtue of your having paid taxes if that is your implication. You would be well-advised to seek a license under the patent and it is likely that government held patents may be licensed.

All valid US Utility Patents have 7 numbers not 6. I dont know what you are referring to. Just be cause it is not enforced does not mean it cant be enforced.

US Utility Patents typically have seven numbers - so "663007" is likely the wrong number. The owner of a US Patent decides if and when to enforce the patent, sometimes often, sometimes never. Patent litigation is expensive. The ownership by the US Dept. of Health and Human Services (HHS) does not alter this reality, there is no dedication to the public unless the owner decides to do that. typically by non-payment of the maintenance fees due at years 4, 8 and 12, calculated from the issue date. If the patent expires due to such non-payment, then the patented invention goes into the public domain, free for all to use.