195581 has 2 divisors, whose sum is σ = 195582. Its totient is φ = 195580.

The previous prime is 195541. The next prime is 195593. The reversal of 195581 is 185591.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 188356 + 7225 = 434^2 + 85^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-195581 is a prime.

It is a super-2 number, since 2×195581² = 76503855122, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a d-powerful number, because it can be written as 1 + 9⁴ + 5⁷ + 5⁷ + 8⁵ + 1 .

It is a Curzon 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 195581.

It is not a weakly prime, because it can be changed into another prime (195511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97790 + 97791.

It is an arithmetic number, because the mean of its divisors is an integer number (97791).

2¹⁹⁵⁵⁸¹ is an apocalyptic number.

It is an amenable number.

195581 is a deficient number, since it is larger than the sum of its proper divisors (1).

195581 is an equidigital number, since it uses as much as digits as its factorization.

195581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1800, while the sum is 29.

The square root of 195581 is about 442.2454069858. The cubic root of 195581 is about 58.0464352671.

The spelling of 195581 in words is "one hundred ninety-five thousand, five hundred eighty-one".