13217509 has 2 divisors, whose sum is σ = 13217510. Its totient is φ = 13217508.

The previous prime is 13217467. The next prime is 13217513. The reversal of 13217509 is 90571231.

13217509 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9941409 + 3276100 = 3153^2 + 1810^2 .

It is a cyclic number.

It is not a de Polignac number, because 13217509 - 2⁹ = 13216997 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13217579) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6608754 + 6608755.

It is an arithmetic number, because the mean of its divisors is an integer number (6608755).

Almost surely, 2^13217509 is an apocalyptic number.

It is an amenable number.

13217509 is a deficient number, since it is larger than the sum of its proper divisors (1).

13217509 is an equidigital number, since it uses as much as digits as its factorization.

13217509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1890, while the sum is 28.

The square root of 13217509 is about 3635.5892232209. The cubic root of 13217509 is about 236.4375977927.

The spelling of 13217509 in words is "thirteen million, two hundred seventeen thousand, five hundred nine".