8117868581909 has 2 divisors, whose sum is σ = 8117868581910. Its totient is φ = 8117868581908.

The previous prime is 8117868581761. The next prime is 8117868582001. The reversal of 8117868581909 is 9091858687118.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6854892694225 + 1262975887684 = 2618185^2 + 1123822^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8117868581909 is a prime.

It is a super-3 number, since 3×8117868581909³ (a number of 40 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8117868580909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4058934290954 + 4058934290955.

It is an arithmetic number, because the mean of its divisors is an integer number (4058934290955).

Almost surely, 2^{8117868581909} is an apocalyptic number.

It is an amenable number.

8117868581909 is a deficient number, since it is larger than the sum of its proper divisors (1).

8117868581909 is an equidigital number, since it uses as much as digits as its factorization.

8117868581909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 69672960, while the sum is 71.

The spelling of 8117868581909 in words is "eight trillion, one hundred seventeen billion, eight hundred sixty-eight million, five hundred eighty-one thousand, nine hundred nine".