809599969 has 2 divisors, whose sum is σ = 809599970. Its totient is φ = 809599968.

The previous prime is 809599961. The next prime is 809600017. The reversal of 809599969 is 969995908.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 772840000 + 36759969 = 27800^2 + 6063^2 .

It is a cyclic number.

It is not a de Polignac number, because 809599969 - 2³ = 809599961 is a prime.

It is a super-3 number, since 3×809599969³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a self number, because there is not a number n which added to its sum of digits gives 809599969.

It is not a weakly prime, because it can be changed into another prime (809599961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 404799984 + 404799985.

It is an arithmetic number, because the mean of its divisors is an integer number (404799985).

Almost surely, 2^809599969 is an apocalyptic number.

It is an amenable number.

809599969 is a deficient number, since it is larger than the sum of its proper divisors (1).

809599969 is an equidigital number, since it uses as much as digits as its factorization.

809599969 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14171760, while the sum is 64.

The square root of 809599969 is about 28453.4702452970. The cubic root of 809599969 is about 932.0162710447.

The spelling of 809599969 in words is "eight hundred nine million, five hundred ninety-nine thousand, nine hundred sixty-nine".