Given the logical underpinning of mathematics, an infinite range of numbers exist that are greater than 1 trillion. On a finite scale, however, the lowest number that is greater than 1 trillion is 1,000,000,000,001. The next order of magnitude is 10 trillion, and the next level of numerals with a name of its own is a quadrillion, which is three orders of magnitude greater than a trillion.
It is difficult for a human mind to grasp the concept of 1 trillion, and the standard numerical depiction of the number, 1,000,000,000,000, is difficult to work with in equations. This is why the number, and most of the numbers above it, is often represented exponentially as 10^12. Higher numbers can be represented either as multiples of 10^12, such as 2.5 x 10^12, which equals 2,500,000,000,000, or as higher exponents such as 10^15, which is a quadrillion.
In long-form number systems, such as that used in continental Europe, 1 trillion is equal to 10^18, or 1 quintillion in the United States. In this system, the next order of magnitude is 1 thousand trillion, or 1 trilliard, which is equal to 10^21. Long-form counting is unusual in English-speaking countries, however, so numbers such as the milliard, billiard and trilliard are not often used.