8643281 has 2 divisors, whose sum is σ = 8643282. Its totient is φ = 8643280.

The previous prime is 8643223. The next prime is 8643287. The reversal of 8643281 is 1823468.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4879681 + 3763600 = 2209^2 + 1940^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8643281 is a prime.

It is a super-2 number, since 2×8643281² = 149412612889922, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (8643287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4321640 + 4321641.

It is an arithmetic number, because the mean of its divisors is an integer number (4321641).

Almost surely, 2^8643281 is an apocalyptic number.

It is an amenable number.

8643281 is a deficient number, since it is larger than the sum of its proper divisors (1).

8643281 is an equidigital number, since it uses as much as digits as its factorization.

8643281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9216, while the sum is 32.

The square root of 8643281 is about 2939.9457477988. The cubic root of 8643281 is about 205.2230845320.

The spelling of 8643281 in words is "eight million, six hundred forty-three thousand, two hundred eighty-one".