195985381 has 2 divisors, whose sum is σ = 195985382. Its totient is φ = 195985380.

The previous prime is 195985331. The next prime is 195985397. The reversal of 195985381 is 183589591.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 184144900 + 11840481 = 13570^2 + 3441^2 .

It is an emirp because it is prime and its reverse (183589591) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 195985381 - 2⁹ = 195984869 is a prime.

It is a super-2 number, since 2×195985381² = 76820539131430322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (195985331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97992690 + 97992691.

It is an arithmetic number, because the mean of its divisors is an integer number (97992691).

Almost surely, 2^195985381 is an apocalyptic number.

It is an amenable number.

195985381 is a deficient number, since it is larger than the sum of its proper divisors (1).

195985381 is an equidigital number, since it uses as much as digits as its factorization.

195985381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 388800, while the sum is 49.

The square root of 195985381 is about 13999.4778831212. The cubic root of 195985381 is about 580.8641310519.

The spelling of 195985381 in words is "one hundred ninety-five million, nine hundred eighty-five thousand, three hundred eighty-one".