10208509 has 2 divisors, whose sum is σ = 10208510. Its totient is φ = 10208508.

The previous prime is 10208507. The next prime is 10208531. The reversal of 10208509 is 90580201.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10208025 + 484 = 3195^2 + 22^2 .

It is a cyclic number.

It is not a de Polignac number, because 10208509 - 2¹ = 10208507 is a prime.

Together with 10208507, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10208507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5104254 + 5104255.

It is an arithmetic number, because the mean of its divisors is an integer number (5104255).

Almost surely, 2^10208509 is an apocalyptic number.

It is an amenable number.

10208509 is a deficient number, since it is larger than the sum of its proper divisors (1).

10208509 is an equidigital number, since it uses as much as digits as its factorization.

10208509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 10208509 is about 3195.0757424512. The cubic root of 10208509 is about 216.9305772957.

The spelling of 10208509 in words is "ten million, two hundred eight thousand, five hundred nine".