809897983 has 2 divisors, whose sum is σ = 809897984. Its totient is φ = 809897982.

The previous prime is 809897947. The next prime is 809897987. The reversal of 809897983 is 389798908.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 809897983 - 2²¹ = 807800831 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (809897987) 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, 404948991 + 404948992.

It is an arithmetic number, because the mean of its divisors is an integer number (404948992).

Almost surely, 2^809897983 is an apocalyptic number.

809897983 is a deficient number, since it is larger than the sum of its proper divisors (1).

809897983 is an equidigital number, since it uses as much as digits as its factorization.

809897983 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7838208, while the sum is 61.

The square root of 809897983 is about 28458.7066290793. The cubic root of 809897983 is about 932.1306155087.

The spelling of 809897983 in words is "eight hundred nine million, eight hundred ninety-seven thousand, nine hundred eighty-three".