28756243 has 2 divisors, whose sum is σ = 28756244. Its totient is φ = 28756242.

The previous prime is 28756223. The next prime is 28756267. The reversal of 28756243 is 34265782.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28756243 - 2⁹ = 28755731 is a prime.

It is a super-2 number, since 2×28756243² = 1653843022950098, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28756213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14378121 + 14378122.

It is an arithmetic number, because the mean of its divisors is an integer number (14378122).

Almost surely, 2^28756243 is an apocalyptic number.

28756243 is a deficient number, since it is larger than the sum of its proper divisors (1).

28756243 is an equidigital number, since it uses as much as digits as its factorization.

28756243 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 80640, while the sum is 37.

The square root of 28756243 is about 5362.4847785332. The cubic root of 28756243 is about 306.3684562998.

The spelling of 28756243 in words is "twenty-eight million, seven hundred fifty-six thousand, two hundred forty-three".