28643 has 2 divisors, whose sum is σ = 28644. Its totient is φ = 28642.

The previous prime is 28631. The next prime is 28649. The reversal of 28643 is 34682.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28643 - 2⁴ = 28627 is a prime.

It is a Sophie Germain prime.

It is an Ulam number.

It is a plaindrome in base 12.

It is not a weakly prime, because it can be changed into another prime (28649) 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, 14321 + 14322.

It is an arithmetic number, because the mean of its divisors is an integer number (14322).

2²⁸⁶⁴³ is an apocalyptic number.

28643 is a deficient number, since it is larger than the sum of its proper divisors (1).

28643 is an equidigital number, since it uses as much as digits as its factorization.

28643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1152, while the sum is 23.

The square root of 28643 is about 169.2424296682. The cubic root of 28643 is about 30.5965764322.

The spelling of 28643 in words is "twenty-eight thousand, six hundred forty-three".