809231899669 has 2 divisors, whose sum is σ = 809231899670. Its totient is φ = 809231899668.

The previous prime is 809231899661. The next prime is 809231899691. The reversal of 809231899669 is 966998132908.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 808404186769 + 827712900 = 899113^2 + 28770^2 .

It is a cyclic number.

It is not a de Polignac number, because 809231899669 - 2³ = 809231899661 is a prime.

It is a super-2 number, since 2×809231899669² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 809231899598 and 809231899607.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (809231899661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 404615949834 + 404615949835.

It is an arithmetic number, because the mean of its divisors is an integer number (404615949835).

Almost surely, 2^809231899669 is an apocalyptic number.

It is an amenable number.

809231899669 is a deficient number, since it is larger than the sum of its proper divisors (1).

809231899669 is an equidigital number, since it uses as much as digits as its factorization.

809231899669 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 90699264, while the sum is 70.

The spelling of 809231899669 in words is "eight hundred nine billion, two hundred thirty-one million, eight hundred ninety-nine thousand, six hundred sixty-nine".