805219009 has 6 divisors (see below), whose sum is σ = 936683394. Its totient is φ = 690187680.

The previous prime is 805219001. The next prime is 805219013. The reversal of 805219009 is 900912508.

It can be written as a sum of positive squares in only one way, i.e., 588305025 + 216913984 = 24255^2 + 14728^2 .

It is not a de Polignac number, because 805219009 - 2³ = 805219001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (805219001) 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 in 5 ways as a sum of consecutive naturals, for example, 8216472 + ... + 8216569.

It is an arithmetic number, because the mean of its divisors is an integer number (156113899).

Almost surely, 2^805219009 is an apocalyptic number.

It is an amenable number.

805219009 is a deficient number, since it is larger than the sum of its proper divisors (131464385).

805219009 is a wasteful number, since it uses less digits than its factorization.

805219009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16433055 (or 16433048 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 34.

The square root of 805219009 is about 28376.3811822438. The cubic root of 805219009 is about 930.3321005327.

The spelling of 805219009 in words is "eight hundred five million, two hundred nineteen thousand, nine".