The Sa'ami languages are grouped with the Finno-Ughric group ~ mostly on the basis of sharing the same vocabularies in a wide variety of human activities.
However, there are sufficient grammatical differences in ALL the Sa'ami languages to set them aside as EARLIER than Finnish, Estonian, and possibly some extinct forms more akin to the Hungarian base language (before the arrival of the Cumin, et al).
Even German has acquired some grammatical forms from Sa'ami ~ which suggests some serious contact about the 8th Century BCE.
Current thinking is the other languages once grouped in the former Uralic-Altaic group probably originated IN THE WEST and then spread EAST.
Even some Japanese (the Royal Family and Daimyo ~ the people who invaded in the 6th century AD) have the Sa'ami X-factor gene sequence, as do the Yakuts/Sakha in Russia, the Iriquois, Cherokee, Ojibway and other Indians in North America, as well as do the Fulbe in Africa, and the Berbers ~ these all being connections as recent as 7,000 years back!
The Sa'ami have no connection with Central and East Asian groups except the Yakuts/Sakha (who are ancestral to the Daimyo BTW).
The archaeological record shows that as fast as the ice melted the people who became the Sa'ami moved NORTH on the Western coast of the Fenno-Scandian peninsula to the Arctic Ocena and then East to more familiar Sa'ami territories.
Check this website: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1199377/
But my overall point is that various peoples from the East have moved into Europe and that these periodic waves of migrations have been taking place for thousands of years and are not any sort of surprising new discovery.
This would seem to be a loanword from an Indo-European language--the Avestan word for 100 is satem, and in several modern Slavic languages the word is sto. This corresponds to the word for 100 in the so-called centum languages (Latin "100 = centum, Greek hekaton, etc.)--there is a pattern of words which have an "s" in Indo-Iranian, Baltic, and Slavic, which have a "k" sound in Greek, Latin, Celtic, etc. (in the Germanic languages the "k" becomes an "h")--for example, Greek kardia for "heart" vs. Russian serdtse or Latvian sirds.
Getting back to the Finnish word for "100" it would appear they didn't have a word for that number so they borrowed it from some ancient Iranian or Slavic speaker. The Scythians were Iranian-speaking and lived north of the Black Sea.