195438581 has 4 divisors (see below), whose sum is σ = 210472332. Its totient is φ = 180404832.

The previous prime is 195438577. The next prime is 195438629. The reversal of 195438581 is 185834591.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 77281681 + 118156900 = 8791^2 + 10870^2 .

It is a cyclic number.

It is not a de Polignac number, because 195438581 - 2² = 195438577 is a prime.

It is a super-2 number, since 2×195438581² = 76392477886587122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (195438281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7516856 + ... + 7516881.

It is an arithmetic number, because the mean of its divisors is an integer number (52618083).

Almost surely, 2^195438581 is an apocalyptic number.

It is an amenable number.

195438581 is a deficient number, since it is larger than the sum of its proper divisors (15033751).

195438581 is a wasteful number, since it uses less digits than its factorization.

195438581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15033750.

The product of its digits is 172800, while the sum is 44.

The square root of 195438581 is about 13979.9349426240. The cubic root of 195438581 is about 580.3234234616.

The spelling of 195438581 in words is "one hundred ninety-five million, four hundred thirty-eight thousand, five hundred eighty-one".