809903 has 2 divisors, whose sum is σ = 809904. Its totient is φ = 809902.

The previous prime is 809891. The next prime is 809909. The reversal of 809903 is 309908.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 809903 - 2⁶ = 809839 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (809909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 404951 + 404952.

It is an arithmetic number, because the mean of its divisors is an integer number (404952).

2⁸⁰⁹⁹⁰³ is an apocalyptic number.

809903 is a deficient number, since it is larger than the sum of its proper divisors (1).

809903 is an equidigital number, since it uses as much as digits as its factorization.

809903 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 809903 is about 899.9461094977. The cubic root of 809903 is about 93.2132540232.

The spelling of 809903 in words is "eight hundred nine thousand, nine hundred three".