195955843561 has 9 divisors (see below), whose sum is σ = 198954322749. Its totient is φ = 193001913324.

The previous prime is 195955843547. The next prime is 195955843571. The reversal of 195955843561 is 165348559591.

The square root of 195955843561 is 442669.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 195955843561 - 2⁵ = 195955843529 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 195955843561.

It is not an unprimeable number, because it can be changed into a prime (195955843571) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 29655520 + ... + 29662126.

It is an arithmetic number, because the mean of its divisors is an integer number (22106035861).

Almost surely, 2^195955843561 is an apocalyptic number.

195955843561 is the 442669-th square number.

195955843561 is the 221335-th centered octagonal number.

It is an amenable number.

195955843561 is a deficient number, since it is larger than the sum of its proper divisors (2998479188).

195955843561 is an frugal number, since it uses more digits than its factorization.

195955843561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13348 (or 6674 counting only the distinct ones).

The product of its digits is 29160000, while the sum is 61.

The spelling of 195955843561 in words is "one hundred ninety-five billion, nine hundred fifty-five million, eight hundred forty-three thousand, five hundred sixty-one".