Question about the Figure 8 song

Is the piano music from -or based on- a classical piece? If so, what one? It reminds me of the piano solo in the song "All By Myself" by Eric Carmen, which according to wikipedia.com, "borrows very heavily from the second movement (Adagio Sostenuto) of Sergei Rachmaninoff's Piano Concerto No. 2 in C minor, Opus 18".