263 (two hundred
ndsixty-three) is the natural number between
262 and
264
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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 ...
. It is also a
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 ...
.
In mathematics
263 is
a
balanced prime,
an
irregular prime,
a
Ramanujan prime, a
Chen prime, and
a
safe prime.
It is also a strictly non-palindromic number and a
happy number
In number theory, a happy number is a number which eventually reaches 1 when the number is replaced by the sum of the square of each digit. For instance, 13 is a happy number because 1^2+3^2=10, and 1^2+0^2=1. On the other hand, 4 is not a happy ...
.
References
Integers
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