318281 has 2 divisors, whose sum is σ = 318282. Its totient is φ = 318280.

The previous prime is 318271. The next prime is 318287. The reversal of 318281 is 182813.

318281 is nontrivially palindromic in base 8.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 292681 + 25600 = 541^2 + 160^2 .

It is an emirp because it is prime and its reverse (182813) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 318281 - 2¹⁰ = 317257 is a prime.

It is a super-2 number, since 2×318281² = 202605589922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a zygodrome in base 8.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 318281.

It is not a weakly prime, because it can be changed into another prime (318287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 159140 + 159141.

It is an arithmetic number, because the mean of its divisors is an integer number (159141).

2³¹⁸²⁸¹ is an apocalyptic number.

It is an amenable number.

318281 is a deficient number, since it is larger than the sum of its proper divisors (1).

318281 is an equidigital number, since it uses as much as digits as its factorization.

318281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 384, while the sum is 23.

The square root of 318281 is about 564.1639832531. The cubic root of 318281 is about 68.2763408726.

The spelling of 318281 in words is "three hundred eighteen thousand, two hundred eighty-one".