528378509 has 2 divisors, whose sum is σ = 528378510. Its totient is φ = 528378508.

The previous prime is 528378491. The next prime is 528378541. The reversal of 528378509 is 905873825.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 421152484 + 107226025 = 20522^2 + 10355^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-528378509 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (528378569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 264189254 + 264189255.

It is an arithmetic number, because the mean of its divisors is an integer number (264189255).

Almost surely, 2^528378509 is an apocalyptic number.

It is an amenable number.

528378509 is a deficient number, since it is larger than the sum of its proper divisors (1).

528378509 is an equidigital number, since it uses as much as digits as its factorization.

528378509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 604800, while the sum is 47.

The square root of 528378509 is about 22986.4853555301. The cubic root of 528378509 is about 808.4410950769.

The spelling of 528378509 in words is "five hundred twenty-eight million, three hundred seventy-eight thousand, five hundred nine".