41 (forty-one) is the
natural number
In mathematics, the natural numbers are the numbers 0, 1, 2, 3, and so on, possibly excluding 0. Some start counting with 0, defining the natural numbers as the non-negative integers , while others start with 1, defining them as the positive in ...
following
40 and preceding
42.
In mathematics
41 is:
* the 13th smallest
prime number
A prime number (or a prime) is a natural number greater than 1 that is not a Product (mathematics), product of two smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number. For example, 5 is prime ...
. The next is
43, making both
twin prime
A twin prime is a prime number that is either 2 less or 2 more than another prime number—for example, either member of the twin prime pair or In other words, a twin prime is a prime that has a prime gap of two. Sometimes the term ''twin prime' ...
s.
* the sum of the first six prime numbers (2 + 3 + 5 + 7 + 11 + 13).
* a
regular prime
* a
Ramanujan prime
* a
harmonic prime
* a
good prime
* the 12th
supersingular prime
* a
Newman–Shanks–Williams prime.
* the smallest
Sophie Germain prime to start a
Cunningham chain of the first kind of three terms, .
* an
Eisenstein prime, with no imaginary part and real part of the form 3''n'' − 1.
* a
Proth prime as it is 5 × 2
3 + 1.
* the smallest
lucky number of Euler: the polynomial yields primes for all the integers ''k'' with .
* the sum of two
squares
In geometry, a square is a regular polygon, regular quadrilateral. It has four straight sides of equal length and four equal angles. Squares are special cases of rectangles, which have four equal angles, and of rhombuses, which have four equal si ...
(4
2 + 5
2), which makes it a
centered square number.
* the sum of the first three
Mersenne prime
In mathematics, a Mersenne prime is a prime number that is one less than a power of two. That is, it is a prime number of the form for some integer . They are named after Marin Mersenne, a French Minim friar, who studied them in the early 1 ...
s, 3, 7, 31.
* the sum of the sum of the divisors of the first 7
positive integers
In mathematics, the natural numbers are the numbers 0, 1, 2, 3, and so on, possibly excluding 0. Some start counting with 0, defining the natural numbers as the non-negative integers , while others start with 1, defining them as the positiv ...
.
* the smallest integer whose reciprocal has a 5-digit
repetend. That is a consequence of the fact that 41 is a factor of 99999.
* the smallest integer whose
square root
In mathematics, a square root of a number is a number such that y^2 = x; in other words, a number whose ''square'' (the result of multiplying the number by itself, or y \cdot y) is . For example, 4 and −4 are square roots of 16 because 4 ...
has a
simple continued fraction
A simple or regular continued fraction is a continued fraction with numerators all equal one, and denominators built from a sequence \ of integer numbers. The sequence can be finite or infinite, resulting in a finite (or terminated) continued fr ...
with
period 3.
* a prime index prime, as 13 is prime.
In other fields
* In Mexico "cuarenta y uno" (41) is slang referring to a
homosexual. This is due to the 1901 arrest of 41 homosexuals at a hotel in
Mexico City
Mexico City is the capital city, capital and List of cities in Mexico, largest city of Mexico, as well as the List of North American cities by population, most populous city in North America. It is one of the most important cultural and finan ...
during the government of Porfirio Díaz (1876–1911). See:
Dance of the Forty-One
* In
Switzerland
Switzerland, officially the Swiss Confederation, is a landlocked country located in west-central Europe. It is bordered by Italy to the south, France to the west, Germany to the north, and Austria and Liechtenstein to the east. Switzerland ...
, is the international calling code
References
{{DEFAULTSORT:41 (Number)
Integers