28005247 has 2 divisors, whose sum is σ = 28005248. Its totient is φ = 28005246.

The previous prime is 28005227. The next prime is 28005269. The reversal of 28005247 is 74250082.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28005247 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28005227) 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, 14002623 + 14002624.

It is an arithmetic number, because the mean of its divisors is an integer number (14002624).

Almost surely, 2^28005247 is an apocalyptic number.

28005247 is a deficient number, since it is larger than the sum of its proper divisors (1).

28005247 is an equidigital number, since it uses as much as digits as its factorization.

28005247 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4480, while the sum is 28.

The square root of 28005247 is about 5291.9983938017. The cubic root of 28005247 is about 303.6778638390.

The spelling of 28005247 in words is "twenty-eight million, five thousand, two hundred forty-seven".