195615784981 has 2 divisors, whose sum is σ = 195615784982. Its totient is φ = 195615784980.

The previous prime is 195615784963. The next prime is 195615784993. The reversal of 195615784981 is 189487516591.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 156859563025 + 38756221956 = 396055^2 + 196866^2 .

It is a cyclic number.

It is not a de Polignac number, because 195615784981 - 2⁷ = 195615784853 is a prime.

It is a super-2 number, since 2×195615784981² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (195615784081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97807892490 + 97807892491.

It is an arithmetic number, because the mean of its divisors is an integer number (97807892491).

Almost surely, 2^195615784981 is an apocalyptic number.

It is an amenable number.

195615784981 is a deficient number, since it is larger than the sum of its proper divisors (1).

195615784981 is an equidigital number, since it uses as much as digits as its factorization.

195615784981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21772800, while the sum is 64.

The spelling of 195615784981 in words is "one hundred ninety-five billion, six hundred fifteen million, seven hundred eighty-four thousand, nine hundred eighty-one".