13491509 has 2 divisors, whose sum is σ = 13491510. Its totient is φ = 13491508.

The previous prime is 13491497. The next prime is 13491529. The reversal of 13491509 is 90519431.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9579025 + 3912484 = 3095^2 + 1978^2 .

It is a cyclic number.

It is not a de Polignac number, because 13491509 - 2²⁰ = 12442933 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13491529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6745754 + 6745755.

It is an arithmetic number, because the mean of its divisors is an integer number (6745755).

Almost surely, 2^13491509 is an apocalyptic number.

It is an amenable number.

13491509 is a deficient number, since it is larger than the sum of its proper divisors (1).

13491509 is an equidigital number, since it uses as much as digits as its factorization.

13491509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4860, while the sum is 32.

The square root of 13491509 is about 3673.0789536845. The cubic root of 13491509 is about 238.0602265020.

The spelling of 13491509 in words is "thirteen million, four hundred ninety-one thousand, five hundred nine".