985805 has 4 divisors (see below), whose sum is σ = 1182972. Its totient is φ = 788640.

The previous prime is 985799. The next prime is 985807. The reversal of 985805 is 508589.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 508589 = 17 ⋅29917.

It can be written as a sum of positive squares in 2 ways, for example, as 779689 + 206116 = 883^2 + 454^2 .

It is not a de Polignac number, because 985805 - 2⁶ = 985741 is a prime.

It is a super-2 number, since 2×985805² = 1943622996050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 985805.

It is not an unprimeable number, because it can be changed into a prime (985807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 98576 + ... + 98585.

It is an arithmetic number, because the mean of its divisors is an integer number (295743).

2⁹⁸⁵⁸⁰⁵ is an apocalyptic number.

It is an amenable number.

985805 is a deficient number, since it is larger than the sum of its proper divisors (197167).

985805 is a wasteful number, since it uses less digits than its factorization.

985805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 197166.

The product of its (nonzero) digits is 14400, while the sum is 35.

The square root of 985805 is about 992.8771323784. The cubic root of 985805 is about 99.5245766416.

The spelling of 985805 in words is "nine hundred eighty-five thousand, eight hundred five".