809450989 has 2 divisors, whose sum is σ = 809450990. Its totient is φ = 809450988.

The previous prime is 809450969. The next prime is 809451001. The reversal of 809450989 is 989054908.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 560126889 + 249324100 = 23667^2 + 15790^2 .

It is a cyclic number.

It is not a de Polignac number, because 809450989 - 2⁷ = 809450861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (809450909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 404725494 + 404725495.

It is an arithmetic number, because the mean of its divisors is an integer number (404725495).

Almost surely, 2^809450989 is an apocalyptic number.

It is an amenable number.

809450989 is a deficient number, since it is larger than the sum of its proper divisors (1).

809450989 is an equidigital number, since it uses as much as digits as its factorization.

809450989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 933120, while the sum is 52.

The square root of 809450989 is about 28450.8521664993. The cubic root of 809450989 is about 931.9590986520.

The spelling of 809450989 in words is "eight hundred nine million, four hundred fifty thousand, nine hundred eighty-nine".