855199809 has 16 divisors (see below), whose sum is σ = 1287735040. Its totient is φ = 560785680.

The previous prime is 855199801. The next prime is 855199811. The reversal of 855199809 is 908991558.

855199809 is a `hidden beast` number, since 8 + 551 + 9 + 9 + 80 + 9 = 666.

It is not a de Polignac number, because 855199809 - 2³ = 855199801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (855199801) 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 in 15 ways as a sum of consecutive naturals, for example, 257977 + ... + 261270.

It is an arithmetic number, because the mean of its divisors is an integer number (80483440).

Almost surely, 2^855199809 is an apocalyptic number.

It is an amenable number.

855199809 is a deficient number, since it is larger than the sum of its proper divisors (432535231).

855199809 is a wasteful number, since it uses less digits than its factorization.

855199809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 519317 (or 519311 counting only the distinct ones).

The product of its (nonzero) digits is 1166400, while the sum is 54.

The square root of 855199809 is about 29243.7994966454. The cubic root of 855199809 is about 949.1959249826.

The spelling of 855199809 in words is "eight hundred fifty-five million, one hundred ninety-nine thousand, eight hundred nine".