The Number
21981
Twenty-One Thousand Nine Hundred and Eighty-One
In Base 18 Octodecimal Is
3df318
The numbers with a 18 subscript use Base 18 Octodecimal notation.
For more familiar numbers: See Twenty-One Thousand Nine Hundred and Eighty-One in Base 10 Decimal
Nearby Numbers
Positive, nonzero integers within three units
Scientific Notation
Scientific notation expresses a quantity as the product of its significand with 10 raised to an integer exponent.
2.1981e4
Reciprocal
A number multiplied with its reciprocal is one.
0.0004dh644gh88fb6818
The reciprocal of 21981 in Base 18 Octodecimal.
Palindrome?
A numerical palindrome has the same value when all of its digits are reversed.
The number 3df318 is not a palindrome.
Not A Prime Number
A prime number is a positive integer that is divisible only by itself and one.
Twenty-one thousand nine hundred and eighty-one is a composite number with 8 total factors (including 1 and itself). See primes in Base 18 Octodecimal
A Composite
Composites have more than just these two factors.
Twenty-one thousand nine hundred and eighty-one is a composite number with 8 total factors (including 1 and itself).
Prime Factors
The number twenty-one thousand nine hundred and eighty-one has the following 3 prime factors:
Prime Factorization
The prime factorization of a positive integer is the unique list of prime factors together with their multiplicities
3181
·
h181
·
15h181
= 3df318
Base Conversions
The number twenty-one thousand nine hundred and eighty-one in 35 different bases