64257509 has 2 divisors, whose sum is σ = 64257510. Its totient is φ = 64257508.

The previous prime is 64257503. The next prime is 64257511. The reversal of 64257509 is 90575246.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 47472100 + 16785409 = 6890^2 + 4097^2 .

It is a cyclic number.

It is not a de Polignac number, because 64257509 - 2¹⁶ = 64191973 is a prime.

Together with 64257511, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64257503) 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, 32128754 + 32128755.

It is an arithmetic number, because the mean of its divisors is an integer number (32128755).

Almost surely, 2^64257509 is an apocalyptic number.

It is an amenable number.

64257509 is a deficient number, since it is larger than the sum of its proper divisors (1).

64257509 is an equidigital number, since it uses as much as digits as its factorization.

64257509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 75600, while the sum is 38.

The square root of 64257509 is about 8016.0781558066. The cubic root of 64257509 is about 400.5357591682.

The spelling of 64257509 in words is "sixty-four million, two hundred fifty-seven thousand, five hundred nine".