9681291817 has 2 divisors, whose sum is σ = 9681291818. Its totient is φ = 9681291816.

The previous prime is 9681291779. The next prime is 9681291827. The reversal of 9681291817 is 7181921869.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9654831081 + 26460736 = 98259^2 + 5144^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9681291817 is a prime.

It is a super-2 number, since 2×9681291817² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (9681291827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4840645908 + 4840645909.

It is an arithmetic number, because the mean of its divisors is an integer number (4840645909).

Almost surely, 2^9681291817 is an apocalyptic number.

It is an amenable number.

9681291817 is a deficient number, since it is larger than the sum of its proper divisors (1).

9681291817 is an equidigital number, since it uses as much as digits as its factorization.

9681291817 is an evil number, because the sum of its binary digits is even.

The product of its digits is 435456, while the sum is 52.

The square root of 9681291817 is about 98393.5557696743. Note that the first 3 decimals coincide. The cubic root of 9681291817 is about 2131.2992739364.

The spelling of 9681291817 in words is "nine billion, six hundred eighty-one million, two hundred ninety-one thousand, eight hundred seventeen".