What comes after quadrillion
Quintillion comes after quadrillion. The name sequence is stable, while the associated power of ten depends on whether short scale or long scale naming is used.
Large-number naming and powers of ten
Large-number names group digits in powers of ten. Scientific notation expresses the same idea with \(10^n\). Two conventions appear in practice:
- Short scale (modern English in many contexts): each new “-illion” increases the exponent by 3.
- Long scale (historical in parts of Europe and some languages): each new “-illion” increases the exponent by 6.
The next name after quadrillion is quintillion in both conventions:
\( \text{quadrillion} \rightarrow \text{quintillion} \)
Visualization: quadrillion → quintillion on short vs long scale
Short scale values (common in modern English usage)
In short scale naming, each “-illion” advances by three powers of ten. The transition from quadrillion to quintillion is:
\[ 10^{15}\ (\text{quadrillion}) \;\rightarrow\; 10^{18}\ (\text{quintillion}) \]
Long scale values (used in some languages and historical contexts)
In long scale naming, each “-illion” advances by six powers of ten. The same next-name relationship appears, with different magnitudes:
\[ 10^{24}\ (\text{quadrillion}) \;\rightarrow\; 10^{30}\ (\text{quintillion}) \]
Reference table of nearby names
| Number name | Short scale (power of ten) | Long scale (power of ten) |
|---|---|---|
| trillion | \(10^{12}\) | \(10^{18}\) |
| quadrillion | \(10^{15}\) | \(10^{24}\) |
| quintillion | \(10^{18}\) | \(10^{30}\) |
| sextillion | \(10^{21}\) | \(10^{36}\) |
Common pitfalls
- Scale mismatch: the name after quadrillion remains quintillion, while the exponent differs by convention.
- Digit grouping confusion: short scale groups by thousands (\(10^3\)) per “-illion,” while long scale advances by million-squared steps (\(10^6\)) per “-illion.”
- Mixed notation: scientific notation \(a \times 10^n\) removes ambiguity when the scale is unclear.
Quintillion is the standard next large-number name after quadrillion, and scientific notation (\(10^n\)) provides an unambiguous statement of magnitude.