The Number

9991

Nine Thousand Nine Hundred and Ninety-One

Nearby Numbers

Positive, nonzero integers within three units

9988
Nine Thousand Nine Hundred and Eighty-Eight
9989
Nine Thousand Nine Hundred and Eighty-Nine
9990
Nine Thousand Nine Hundred and Ninety
9992
Nine Thousand Nine Hundred and Ninety-Two
9993
Nine Thousand Nine Hundred and Ninety-Three
9994
Nine Thousand Nine Hundred and Ninety-Four

Scientific Notation

Scientific notation expresses a quantity as the product of its significand with 10 raised to an integer exponent.

9.991e3

Reciprocal

A number multiplied with its reciprocal is one.

0.00010009008107296567

The reciprocal of 9991.

Palindrome?

A numerical palindrome has the same value when all of its digits are reversed.

The number 9991 is not a palindrome.

Not A Prime Number

A prime number is a positive integer that is divisible only by itself and one.

Nine thousand nine hundred and ninety-one is a composite number with 4 total factors (including 1 and itself).   See primes in Base 10 Decimal

A Composite

Composites have more than just these two factors.

Nine thousand nine hundred and ninety-one is a composite number with 4 total factors (including 1 and itself).

Prime Factors

The prime factors of a positive integer are the integers that divide it exactly and are also prime.

The number nine thousand nine hundred and ninety-one has the following 2 prime factors:

97
Ninety-Seven
103
One Hundred and Three

Prime Factorization

The prime factorization of a positive integer is the unique list of prime factors together with their multiplicities

971 · 1031 = 9991

Base Conversions

The number nine thousand nine hundred and ninety-one in 35 different bases