195805 has 4 divisors (see below), whose sum is σ = 234972. Its totient is φ = 156640.

The previous prime is 195791. The next prime is 195809. The reversal of 195805 is 508591.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 508591 = 73 ⋅6967.

It can be written as a sum of positive squares in 2 ways, for example, as 79524 + 116281 = 282^2 + 341^2 .

It is not a de Polignac number, because 195805 - 2⁷ = 195677 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (195809) 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 3 ways as a sum of consecutive naturals, for example, 19576 + ... + 19585.

It is an arithmetic number, because the mean of its divisors is an integer number (58743).

2¹⁹⁵⁸⁰⁵ is an apocalyptic number.

It is an amenable number.

195805 is a deficient number, since it is larger than the sum of its proper divisors (39167).

195805 is an equidigital number, since it uses as much as digits as its factorization.

195805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39166.

The product of its (nonzero) digits is 1800, while the sum is 28.

The square root of 195805 is about 442.4985875684. The cubic root of 195805 is about 58.0685871133.

It can be divided in two parts, 195 and 805, that added together give a cube (1000 = 10³).

The spelling of 195805 in words is "one hundred ninety-five thousand, eight hundred five".