195819596221 has 2 divisors, whose sum is σ = 195819596222. Its totient is φ = 195819596220.

The previous prime is 195819596207. The next prime is 195819596227. The reversal of 195819596221 is 122695918591.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 191856264196 + 3963332025 = 438014^2 + 62955^2 .

It is an emirp because it is prime and its reverse (122695918591) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-195819596221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (195819596227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97909798110 + 97909798111.

It is an arithmetic number, because the mean of its divisors is an integer number (97909798111).

Almost surely, 2^195819596221 is an apocalyptic number.

It is an amenable number.

195819596221 is a deficient number, since it is larger than the sum of its proper divisors (1).

195819596221 is an equidigital number, since it uses as much as digits as its factorization.

195819596221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3499200, while the sum is 58.

The spelling of 195819596221 in words is "one hundred ninety-five billion, eight hundred nineteen million, five hundred ninety-six thousand, two hundred twenty-one".