The Number

21391

Twenty-One Thousand Three Hundred and Ninety-One

Nearby Numbers

Positive, nonzero integers within three units

21388
Twenty-One Thousand Three Hundred and Eighty-Eight
21389
Twenty-One Thousand Three Hundred and Eighty-Nine
21390
Twenty-One Thousand Three Hundred and Ninety
21392
Twenty-One Thousand Three Hundred and Ninety-Two
21393
Twenty-One Thousand Three Hundred and Ninety-Three
21394
Twenty-One Thousand 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.

2.1391e4

Reciprocal

A number multiplied with its reciprocal is one.

0.000046748632602496374

The reciprocal of 21391.

Palindrome?

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

The number 21391 is not a palindrome.

A Prime Number

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

Twenty-one thousand three hundred and ninety-one is the 2401st prime number.   See primes in Base 10 Decimal

Not A Composite

Composites have more than just these two factors.

Twenty-One Thousand Three Hundred and Ninety-One is not a composite number because it has exactly two factors: One and Twenty-One Thousand Three Hundred and Ninety-One

Prime Factors

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

The number twenty-one thousand three hundred and ninety-one has the following 1 prime factor:

21391
Twenty-One Thousand Three Hundred and Ninety-One

Prime Factorization

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

213911 = 21391

Base Conversions

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