400 trillion in scientific notation is 4 ×10144\times 10^{14}4×1014. That is also read as four hundred trillion in standard form, or 4e14 in calculator notation.

In simple terms

  • 400 trillion = 400,000,000,000,000.
  • Move the decimal so the number is between 1 and 10: 4.0.
  • Count the moves: 14 places.

Naming it by powers of ten

  • 101210^{12}1012 is trillion.
  • 101410^{14}1014 is one hundred trillion.
  • So 400 trillion becomes 4×10144\times 10^{14}4×1014, not a special new name beyond scientific notation.

Quick example

  • 4 × 10^{14} = 400,000,000,000,000.

TL;DR: 400 trillion = 4×10144\times 10^{14}4×1014.