The Number

21991

Twenty-One Thousand Nine Hundred and Ninety-One

In Base 6 Senary Is

2454516

The numbers with a 6 subscript use Base 6 Senary notation.

For more familiar numbers: See Twenty-One Thousand Nine Hundred and Ninety-One in Base 10 Decimal

Nearby Numbers

Positive, nonzero integers within three units

21988
2454446
Twenty-One Thousand Nine Hundred and Eighty-Eight in Base 6 Senary
21989
2454456
Twenty-One Thousand Nine Hundred and Eighty-Nine in Base 6 Senary
21990
2454506
Twenty-One Thousand Nine Hundred and Ninety in Base 6 Senary
21992
2454526
Twenty-One Thousand Nine Hundred and Ninety-Two in Base 6 Senary
21993
2454536
Twenty-One Thousand Nine Hundred and Ninety-Three in Base 6 Senary
21994
2454546
Twenty-One Thousand Nine Hundred and Ninety-Four in Base 6 Senary

Scientific Notation

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

2.1991e4

Reciprocal

A number multiplied with its reciprocal is one.

0.000002042133051235120510546

The reciprocal of 21991 in Base 6 Senary.

Palindrome?

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

The number 2454516 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 nine hundred and ninety-one is the 2463rd prime number.   See primes in Base 6 Senary

Not A Composite

Composites have more than just these two factors.

Twenty-One Thousand Nine Hundred and Ninety-One is not a composite number because it has exactly two factors: One and Twenty-One Thousand Nine 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 nine hundred and ninety-one has the following 1 prime factor:

21991
2454516
Twenty-One Thousand Nine Hundred and Ninety-One in Base 6 Senary

Prime Factorization

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

24545161 = 2454516

Base Conversions

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