9281 has 2 divisors, whose sum is σ = 9282.
Its totient is φ = 9280.
The previous prime is 9277. The next prime is 9283. The reversal of 9281 is 1829.
Subtracting from 9281 its sum of digits (20), we obtain a cube (9261 = 213).
It can be divided in two parts, 928 and 1, that added together give a palindrome (929).
9281 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 9025 + 256 = 95^2 + 16^2
It is a cyclic number.
It is not a de Polignac number, because 9281 - 22 = 9277 is a prime.
It is a super-2 number, since 2×92812 = 172273922, which contains 22 as substring.
Together with 9283, it forms a pair of twin primes.
It is a Chen prime.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (9283) by changing a digit.
It is an upside-down number.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4640 + 4641.
It is an arithmetic number, because the mean of its divisors is an integer number (4641).
29281 is an apocalyptic number.
It is an amenable number.
9281 is a deficient number, since it is larger than the sum of its proper divisors (1).
9281 is an equidigital number, since it uses as much as digits as its factorization.
9281 is an evil number, because the sum of its binary digits is even.
The product of its digits is 144, while the sum is 20.
The square root of 9281 is about 96.3379468330.
The cubic root of 9281 is about 21.0151062887.
The spelling of 9281 in words is "nine thousand, two hundred eighty-one".