195997889 has 2 divisors, whose sum is σ = 195997890. Its totient is φ = 195997888.

The previous prime is 195997859. The next prime is 195997931. The reversal of 195997889 is 988799591.

195997889 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 192987664 + 3010225 = 13892^2 + 1735^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-195997889 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (195997859) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97998944 + 97998945.

It is an arithmetic number, because the mean of its divisors is an integer number (97998945).

Almost surely, 2^195997889 is an apocalyptic number.

It is an amenable number.

195997889 is a deficient number, since it is larger than the sum of its proper divisors (1).

195997889 is an equidigital number, since it uses as much as digits as its factorization.

195997889 is an evil number, because the sum of its binary digits is even.

The product of its digits is 14696640, while the sum is 65.

The square root of 195997889 is about 13999.9246069399. The cubic root of 195997889 is about 580.8764879158.

The spelling of 195997889 in words is "one hundred ninety-five million, nine hundred ninety-seven thousand, eight hundred eighty-nine".