855805 has 4 divisors (see below), whose sum is σ = 1026972. Its totient is φ = 684640.

The previous prime is 855787. The next prime is 855821. The reversal of 855805 is 508558.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 508558 = 2 ⋅254279.

It can be written as a sum of positive squares in 2 ways, for example, as 155236 + 700569 = 394^2 + 837^2 .

It is not a de Polignac number, because 855805 - 2⁹ = 855293 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 85576 + ... + 85585.

It is an arithmetic number, because the mean of its divisors is an integer number (256743).

2⁸⁵⁵⁸⁰⁵ is an apocalyptic number.

It is an amenable number.

855805 is a deficient number, since it is larger than the sum of its proper divisors (171167).

855805 is a wasteful number, since it uses less digits than its factorization.

855805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171166.

The product of its (nonzero) digits is 8000, while the sum is 31.

The square root of 855805 is about 925.0972921807. The cubic root of 855805 is about 94.9419774963.

The spelling of 855805 in words is "eight hundred fifty-five thousand, eight hundred five".