6442520509 has 2 divisors, whose sum is σ = 6442520510. Its totient is φ = 6442520508.

The previous prime is 6442520473. The next prime is 6442520521. The reversal of 6442520509 is 9050252446.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6403520484 + 39000025 = 80022^2 + 6245^2 .

It is a cyclic number.

It is not a de Polignac number, because 6442520509 - 2⁹ = 6442519997 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6442520309) 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, 3221260254 + 3221260255.

It is an arithmetic number, because the mean of its divisors is an integer number (3221260255).

Almost surely, 2^6442520509 is an apocalyptic number.

It is an amenable number.

6442520509 is a deficient number, since it is larger than the sum of its proper divisors (1).

6442520509 is an equidigital number, since it uses as much as digits as its factorization.

6442520509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 86400, while the sum is 37.

The square root of 6442520509 is about 80265.3132367899. The cubic root of 6442520509 is about 1860.7381843725.

The spelling of 6442520509 in words is "six billion, four hundred forty-two million, five hundred twenty thousand, five hundred nine".