How many digits does a Octillion have?

A quintillion has 28 digits in total — that’s the digit followed by 27 zeros.

How Many Zeros in a Octillion?

Q: How Many Zeros in a Octillion?

There are 27 zeros in a octillion.

Q: What Comes Before Octillion?

The number that comes before an octillion is a septillion.

Q: What Comes After Octillion?

The next number after an octillion is a nonillion.

The Short Answer: an octillion has 27 zeros in the U.S. numbering system.

It's written as: 1,000,000,000,000,000,000,000,000,000

Scientific notation: 10^27

What Is an Octillion?

"Oct-" means eight, and octillion is the eighth number in the "illion" sequence:

Million – 10⁶
Billion – 10⁹
... up to Octillion – 10²⁷

It is rarely used outside of theoretical math, astronomy, or speculative estimates of scale.

How to Write an Octillion

In full numeric form: 1,000,000,000,000,000,000,000,000,000

That's a 1 followed by 27 zeros.

Octillion Comparison Table

Number Name	Value	Zeros
Million	1,000,000	6
Billion	1,000,000,000	9
Trillion	1,000,000,000,000	12
Quadrillion	1,000,000,000,000,000	15
Quintillion	1,000,000,000,000,000,000	18
Sextillion	1,000,000,000,000,000,000,000	21
Septillion	1,000,000,000,000,000,000,000,000	24
Octillion	1,000,000,000,000,000,000,000,000,000	27

Real-World Context

Appears in cosmic-scale theories and quantum physics calculations
Too large for typical economic or computing use

Octillion Summary

Octillion = 1 followed by 27 zeros
Scientific notation: 10^27
Larger than septillion, smaller than nonillion

Octillion is a symbolic milestone in the sequence of large numbers — more useful for theory than real-world math, but awe-inspiring nonetheless.

Questions & Answers for Octillion

What Comes Before Octillion?

The number that comes before an octillion is a septillion.

Septillion = 1,000,000,000,000,000,000,000,000 (that's 24 zeros)
It's written as 10²⁴ in scientific notation

An octillion is a thousand septillions.

What Comes After Octillion?

The next number after an octillion is a nonillion.

Nonillion = 1,000,000,000,000,000,000,000,000,000 (that's 30 zeros)
It's written as 10³⁰

A nonillion is a thousand octillions.

How many zeros in 2 octillion?

2 octillion = 2,000,000,000,000,000,000,000,000,000
That's a 2 followed by 27 zeros.

How many zeros in 10 octillion?

10 octillion = 10,000,000,000,000,000,000,000,000,000
That's a 1 followed by 28 zeros.

How many zeros in 100 octillion?

100 octillion = 100,000,000,000,000,000,000,000,000,000
That's a 1 followed by 29 zeros.

How many zeros in half an octillion?

0.5 octillion = 500,000,000,000,000,000,000,000,000
That's a 5 followed by 26 zeros.

How many zeros in an octillion in the British system?

Historically in the British long scale, an octillion meant 10^48 — 1 followed by 48 zeros. Today, the UK uses the short scale: 1 followed by 27 zeros.