195748781 has 2 divisors, whose sum is σ = 195748782. Its totient is φ = 195748780.

The previous prime is 195748747. The next prime is 195748793. The reversal of 195748781 is 187847591.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 192959881 + 2788900 = 13891^2 + 1670^2 .

It is an emirp because it is prime and its reverse (187847591) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-195748781 is a prime.

It is a super-2 number, since 2×195748781² = 76635170525971922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (195748381) 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 as a sum of consecutive naturals, namely, 97874390 + 97874391.

It is an arithmetic number, because the mean of its divisors is an integer number (97874391).

Almost surely, 2^195748781 is an apocalyptic number.

It is an amenable number.

195748781 is a deficient number, since it is larger than the sum of its proper divisors (1).

195748781 is an equidigital number, since it uses as much as digits as its factorization.

195748781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 564480, while the sum is 50.

The square root of 195748781 is about 13991.0250160594. The cubic root of 195748781 is about 580.6302908302.

The spelling of 195748781 in words is "one hundred ninety-five million, seven hundred forty-eight thousand, seven hundred eighty-one".