Definition of



A million millions.

1,000,000 x 1,000,000 = 1,000,000,000,000

Which is a 1 followed by 12 zeros.

Using scientific notation: 1 × 1012

We could also think of it as a thousand billions.

• the Andromeda Galaxy contains about a trillion stars
• it is about a trillion meters from Earth to Saturn
• there are around 3 trillion trees on Earth
• there are around 3 trillion fish in the ocean
• the human body has around 100 trillion cells (about 90 trillion are bacteria)

The prefix "tera-" means a trillion. Example: a terameter is a trillion meters.

(In many non-English speaking countries a trillion means a million million million, which is a 1 followed by 18 zeros, or 1 × 1018)

Below is a cube made of a million smaller cubes. If each of the small cubes is also worth a million dollars, then the whole cube is worth a trillion dollars.