768404809 has 2 divisors, whose sum is σ = 768404810. Its totient is φ = 768404808.

The previous prime is 768404807. The next prime is 768404867. The reversal of 768404809 is 908404867.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 585398025 + 183006784 = 24195^2 + 13528^2 .

It is an emirp because it is prime and its reverse (908404867) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 768404809 - 2¹ = 768404807 is a prime.

Together with 768404807, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (768404801) 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, 384202404 + 384202405.

It is an arithmetic number, because the mean of its divisors is an integer number (384202405).

Almost surely, 2^768404809 is an apocalyptic number.

It is an amenable number.

768404809 is a deficient number, since it is larger than the sum of its proper divisors (1).

768404809 is an equidigital number, since it uses as much as digits as its factorization.

768404809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 387072, while the sum is 46.

The square root of 768404809 is about 27720.1156022121. The cubic root of 768404809 is about 915.9322653047.

The spelling of 768404809 in words is "seven hundred sixty-eight million, four hundred four thousand, eight hundred nine".