The Number

391

Three Hundred and Ninety-One

Nearby Numbers

Positive, nonzero integers within three units

388
Three Hundred and Eighty-Eight
389
Three Hundred and Eighty-Nine
390
Three Hundred and Ninety
392
Three Hundred and Ninety-Two
393
Three Hundred and Ninety-Three
394
Three Hundred and Ninety-Four

Scientific Notation

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

3.91e2

Reciprocal

A number multiplied with its reciprocal is one.

0.0025575447570332483

The reciprocal of 391.

Palindrome?

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

The number 391 is not a palindrome.

Not A Prime Number

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

Three 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.

Three 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 three hundred and ninety-one has the following 2 prime factors:

17
Seventeen
23
Twenty-Three

Prime Factorization

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

171 · 231 = 391

Base Conversions

The number three hundred and ninety-one in 35 different bases