8105517355681 has 4 divisors (see below), whose sum is σ = 8112006962500. Its totient is φ = 8099027748864.

The previous prime is 8105517355651. The next prime is 8105517355699. The reversal of 8105517355681 is 1865537155018.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4033031914081 + 4072485441600 = 2008241^2 + 2018040^2 .

It is a cyclic number.

It is not a de Polignac number, because 8105517355681 - 2⁷ = 8105517355553 is a prime.

It is a super-2 number, since 2×8105517355681² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8105517355631) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3244801536 + ... + 3244804033.

It is an arithmetic number, because the mean of its divisors is an integer number (2028001740625).

Almost surely, 2^{8105517355681} is an apocalyptic number.

It is an amenable number.

8105517355681 is a deficient number, since it is larger than the sum of its proper divisors (6489606819).

8105517355681 is a wasteful number, since it uses less digits than its factorization.

8105517355681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6489606818.

The product of its (nonzero) digits is 5040000, while the sum is 55.

The spelling of 8105517355681 in words is "eight trillion, one hundred five billion, five hundred seventeen million, three hundred fifty-five thousand, six hundred eighty-one".