1328909689 has 2 divisors, whose sum is σ = 1328909690. Its totient is φ = 1328909688.

The previous prime is 1328909633. The next prime is 1328909713. The reversal of 1328909689 is 9869098231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1325542464 + 3367225 = 36408^2 + 1835^2 .

It is an emirp because it is prime and its reverse (9869098231) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1328909689 - 2¹¹ = 1328907641 is a prime.

It is not a weakly prime, because it can be changed into another prime (1328909089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 664454844 + 664454845.

It is an arithmetic number, because the mean of its divisors is an integer number (664454845).

Almost surely, 2^1328909689 is an apocalyptic number.

It is an amenable number.

1328909689 is a deficient number, since it is larger than the sum of its proper divisors (1).

1328909689 is an equidigital number, since it uses as much as digits as its factorization.

1328909689 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1679616, while the sum is 55.

The square root of 1328909689 is about 36454.2135973333. The cubic root of 1328909689 is about 1099.4238550356.

The spelling of 1328909689 in words is "one billion, three hundred twenty-eight million, nine hundred nine thousand, six hundred eighty-nine".