# 8191

## 8,191 is a prime number. Like all primes greater than two, it is odd and has no factors apart from itself and one.

What does the number 8191 look like?

As a prime, it is not composed of any other numbers and has no internal structure.

8191 is a prime number. Like all primes (except two), it is an odd number.

## Prime factorization of 8191:

### 8191

See below for interesting mathematical facts about the number 8191 from the Numbermatics database.

### Names of 8191

• Cardinal: 8191 can be written as Eight thousand, one hundred ninety-one.

### Scientific notation

• Scientific notation: 8.191 × 103

### Factors of 8191

• Number of distinct prime factors ω(n): 1
• Total number of prime factors Ω(n): 1
• Sum of prime factors: 8191

### Divisors of 8191

• Number of divisors d(n): 2
• Complete list of divisors:
• Sum of all divisors σ(n): 8192
• Sum of proper divisors (its aliquot sum) s(n): 1
• 8191 is a deficient number, because the sum of its proper divisors (1) is less than itself. Its deficiency is 8190

### Bases of 8191

• Binary: 11111111111112
• Base-36: 6BJ

### Squares and roots of 8191

• 8191 squared (81912) is 67092481
• 8191 cubed (81913) is 549554511871
• The square root of 8191 is 90.5041435515
• The cube root of 8191 is 20.1579165039

### Scales and comparisons

How big is 8191?
• 8,191 seconds is equal to 2 hours, 16 minutes, 31 seconds.
• To count from 1 to 8,191 would take you about two hours.

This is a very rough estimate, based on a speaking rate of half a second every third order of magnitude. If you speak quickly, you could probably say any randomly-chosen number between one and a thousand in around half a second. Very big numbers obviously take longer to say, so we add half a second for every extra x1000. (We do not count involuntary pauses, bathroom breaks or the necessity of sleep in our calculation!)

• A cube with a volume of 8191 cubic inches would be around 1.7 feet tall.

### Recreational maths with 8191

• 8191 backwards is 1918
• The number of decimal digits it has is: 4
• The sum of 8191's digits is 19
• More coming soon!