195309 has 6 divisors (see below), whose sum is σ = 282126. Its totient is φ = 130200.

The previous prime is 195281. The next prime is 195311. The reversal of 195309 is 903591.

It can be written as a sum of positive squares in only one way, i.e., 189225 + 6084 = 435^2 + 78^2 .

It is not a de Polignac number, because 195309 - 2⁵ = 195277 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (195319) 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 5 ways as a sum of consecutive naturals, for example, 10842 + ... + 10859.

It is an arithmetic number, because the mean of its divisors is an integer number (47021).

2¹⁹⁵³⁰⁹ is an apocalyptic number.

It is an amenable number.

195309 is a deficient number, since it is larger than the sum of its proper divisors (86817).

195309 is a wasteful number, since it uses less digits than its factorization.

195309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21707 (or 21704 counting only the distinct ones).

The product of its (nonzero) digits is 1215, while the sum is 27.

The square root of 195309 is about 441.9377784259. The cubic root of 195309 is about 58.0195138461.

The spelling of 195309 in words is "one hundred ninety-five thousand, three hundred nine".