1329128509 has 2 divisors, whose sum is σ = 1329128510. Its totient is φ = 1329128508.

The previous prime is 1329128477. The next prime is 1329128519. The reversal of 1329128509 is 9058219231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1199236900 + 129891609 = 34630^2 + 11397^2 .

It is an emirp because it is prime and its reverse (9058219231) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1329128509 - 2⁵ = 1329128477 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1329128519) 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, 664564254 + 664564255.

It is an arithmetic number, because the mean of its divisors is an integer number (664564255).

Almost surely, 2^1329128509 is an apocalyptic number.

It is an amenable number.

1329128509 is a deficient number, since it is larger than the sum of its proper divisors (1).

1329128509 is an equidigital number, since it uses as much as digits as its factorization.

1329128509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 38880, while the sum is 40.

The square root of 1329128509 is about 36457.2147729362. The cubic root of 1329128509 is about 1099.4841959117.

The spelling of 1329128509 in words is "one billion, three hundred twenty-nine million, one hundred twenty-eight thousand, five hundred nine".