Orders of Magnitude (numbers)

1012

(1000000000000; 10004; short scale: one trillion; long scale: one billion)

ISO: tera- (T)

Astronomy: Andromeda Galaxy, which is part of the same Local Group as our galaxy, contains about 1012 stars.
BioMed — Bacteria on the human body: The surface of the human body houses roughly 1012 bacteria.
Marine biology: 3,500,000,000,000 (3.5 × 1012) – estimated population of fish in the ocean.
Mathematics — Known digits of π: As of 2010, the number of known digits of π is 5,000,000,000,000 (5×1012).
Mathematics: 7,625,597,484,987 – a number that often appears when dealing with powers of 3. It can be expressed as, and 33 or when using Knuth's up-arrow notation it can be expressed as $3 \uparrow\uparrow 3$ and $3 \uparrow\uparrow\uparrow 2$ .
Mathematics: 1013 – The approximate number of known non-trivial zeros of the Riemann zeta function as of 2004.
BioMed — Cells in the human body: The human body consists of roughly 1014 cells, of which only 1013 are human. The remaining 90% non-human cells (though much smaller and constituting much less mass) are bacteria, which mostly reside in the gastrointestinal tract, although the skin is also covered in bacteria.
Computing – MAC-48: 281,474,976,710,656 (248) possible unique physical addresses.
Mathematics: 953,467,954,114,363 is the largest known Motzkin prime.

Orders of Magnitude (numbers) - 1012