265 (two hundred ndsixty-five) 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

264 __NOTOC__ Year 264 (Roman numerals, CCLXIV) was a leap year starting on Friday of the Julian calendar. At the time, it was known as the Year of the Consulship of Gallienus and Saturninus (or, less frequently, year 1017 ''Ab urbe condita''). The ...

and preceding 266.

In mathematics

*265 is an odd

composite number A composite number is a positive integer that can be formed by multiplying two smaller positive integers. Accordingly it is a positive integer that has at least one divisor other than 1 and itself. Every positive integer is composite, prime numb ...

with two prime factors. *265's sum of its proper divisors is 59. *265 is the number of derangements possible with 6 digits. That means that it is equivalent to !6. *The number 265 is associated with the geometric shape known as the

Vesica Piscis The vesica piscis is a type of lens, a mathematical shape formed by the intersection of two disks with the same radius, intersecting in such a way that the center of each disk lies on the perimeter of the other. In Latin, "" literally means "bla ...

. This is shown by having 2 circles overlap in a way that the

circumference In geometry, the circumference () is the perimeter of a circle or ellipse. The circumference is the arc length of the circle, as if it were opened up and straightened out to a line segment. More generally, the perimeter is the curve length arou ...

of each circle touches the center of the other.

Archimedes Archimedes of Syracuse ( ; ) was an Ancient Greece, Ancient Greek Greek mathematics, mathematician, physicist, engineer, astronomer, and Invention, inventor from the ancient city of Syracuse, Sicily, Syracuse in History of Greek and Hellenis ...

estimated that the ratio of the height of this shape to the width was 265:153 or approximately √3. *265 is the 22nd Padovan number which is defined by the two equations P(0)=P(1)=P(2)=1 and P(n)=P(n-2)+P(n-3) similar to the

Fibonacci sequence In mathematics, the Fibonacci sequence is a Integer sequence, sequence in which each element is the sum of the two elements that precede it. Numbers that are part of the Fibonacci sequence are known as Fibonacci numbers, commonly denoted . Many w ...

. *265 is the 7th number to be the

hypotenuse In geometry, a hypotenuse is the side of a right triangle opposite to the right angle. It is the longest side of any such triangle; the two other shorter sides of such a triangle are called '' catheti'' or ''legs''. Every rectangle can be divided ...

for two separate Pythagorean Triples. The other two values would be 23 and

or 96 and 247. *265 is the sum of two sets of two perfect squares. Those being 11 and 12 or 16 and 3. *265 is palindromic in base 12 (1A1).

References

{{Integers, 2 Integers