195390231818 has 4 divisors (see below), whose sum is σ = 293085347730. Its totient is φ = 97695115908.

The previous prime is 195390231811. The next prime is 195390231823. The reversal of 195390231818 is 818132093591.

195390231818 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 818132093591 = 2371 ⋅345057821.

It can be written as a sum of positive squares in only one way, i.e., 194469534169 + 920697649 = 440987^2 + 30343^2 .

It is not an unprimeable number, because it can be changed into a prime (195390231811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 48847557953 + ... + 48847557956.

Almost surely, 2^195390231818 is an apocalyptic number.

195390231818 is a deficient number, since it is larger than the sum of its proper divisors (97695115912).

195390231818 is an equidigital number, since it uses as much as digits as its factorization.

195390231818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97695115911.

The product of its (nonzero) digits is 466560, while the sum is 50.

The spelling of 195390231818 in words is "one hundred ninety-five billion, three hundred ninety million, two hundred thirty-one thousand, eight hundred eighteen".