The Number

21881

Twenty-One Thousand Eight Hundred and Eighty-One

Nearby Numbers

Positive, nonzero integers within three units

21878
Twenty-One Thousand Eight Hundred and Seventy-Eight
21879
Twenty-One Thousand Eight Hundred and Seventy-Nine
21880
Twenty-One Thousand Eight Hundred and Eighty
21882
Twenty-One Thousand Eight Hundred and Eighty-Two
21883
Twenty-One Thousand Eight Hundred and Eighty-Three
21884
Twenty-One Thousand Eight Hundred and Eighty-Four

Scientific Notation

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

2.1881e4

Reciprocal

A number multiplied with its reciprocal is one.

0.000045701750377039444

The reciprocal of 21881.

Palindrome?

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

The number 21881 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 eight hundred and eighty-one is the 2455th prime number.   See primes in Base 10 Decimal

Not A Composite

Composites have more than just these two factors.

Twenty-One Thousand Eight Hundred and Eighty-One is not a composite number because it has exactly two factors: One and Twenty-One Thousand Eight Hundred and Eighty-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 eight hundred and eighty-one has the following 1 prime factor:

21881
Twenty-One Thousand Eight Hundred and Eighty-One

Prime Factorization

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

218811 = 21881

Base Conversions

The number twenty-one thousand eight hundred and eighty-one in 35 different bases