28540643 has 2 divisors, whose sum is σ = 28540644. Its totient is φ = 28540642.

The previous prime is 28540627. The next prime is 28540657. The reversal of 28540643 is 34604582.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28540643 - 2⁴ = 28540627 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (28540693) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14270321 + 14270322.

It is an arithmetic number, because the mean of its divisors is an integer number (14270322).

Almost surely, 2^28540643 is an apocalyptic number.

28540643 is a deficient number, since it is larger than the sum of its proper divisors (1).

28540643 is an equidigital number, since it uses as much as digits as its factorization.

28540643 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23040, while the sum is 32.

The square root of 28540643 is about 5342.3443355890. The cubic root of 28540643 is about 305.6008686860.

The spelling of 28540643 in words is "twenty-eight million, five hundred forty thousand, six hundred forty-three".