28520839 has 2 divisors, whose sum is σ = 28520840. Its totient is φ = 28520838.

The previous prime is 28520827. The next prime is 28520857. The reversal of 28520839 is 93802582.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28520839 - 2⁷ = 28520711 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 28520798 and 28520807.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28520809) 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, 14260419 + 14260420.

It is an arithmetic number, because the mean of its divisors is an integer number (14260420).

Almost surely, 2^28520839 is an apocalyptic number.

28520839 is a deficient number, since it is larger than the sum of its proper divisors (1).

28520839 is an equidigital number, since it uses as much as digits as its factorization.

28520839 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34560, while the sum is 37.

The square root of 28520839 is about 5340.4905205421. The cubic root of 28520839 is about 305.5301681068.

The spelling of 28520839 in words is "twenty-eight million, five hundred twenty thousand, eight hundred thirty-nine".