13520509 has 2 divisors, whose sum is σ = 13520510. Its totient is φ = 13520508.

The previous prime is 13520497. The next prime is 13520531. The reversal of 13520509 is 90502531.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13505625 + 14884 = 3675^2 + 122^2 .

It is a cyclic number.

It is not a de Polignac number, because 13520509 - 2⁵ = 13520477 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13520579) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6760254 + 6760255.

It is an arithmetic number, because the mean of its divisors is an integer number (6760255).

Almost surely, 2^13520509 is an apocalyptic number.

It is an amenable number.

13520509 is a deficient number, since it is larger than the sum of its proper divisors (1).

13520509 is an equidigital number, since it uses as much as digits as its factorization.

13520509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1350, while the sum is 25.

The square root of 13520509 is about 3677.0244763939. The cubic root of 13520509 is about 238.2306745948.

The spelling of 13520509 in words is "thirteen million, five hundred twenty thousand, five hundred nine".