6840805116861 has 6 divisors (see below), whose sum is σ = 9881162946590. Its totient is φ = 4560536744568.

The previous prime is 6840805116799. The next prime is 6840805116869. The reversal of 6840805116861 is 1686115080486.

6840805116861 is a `hidden beast` number, since 6 + 8 + 4 + 0 + 8 + 0 + 511 + 68 + 61 = 666.

It can be written as a sum of positive squares in only one way, i.e., 6460843828761 + 379961288100 = 2541819^2 + 616410^2 .

It is not a de Polignac number, because 6840805116861 - 2¹¹ = 6840805114813 is a prime.

It is a super-2 number, since 2×6840805116861² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6840805116798 and 6840805116807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6840805116869) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 380044728706 + ... + 380044728723.

Almost surely, 2^{6840805116861} is an apocalyptic number.

It is an amenable number.

6840805116861 is a deficient number, since it is larger than the sum of its proper divisors (3040357829729).

6840805116861 is a wasteful number, since it uses less digits than its factorization.

6840805116861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 760089457435 (or 760089457432 counting only the distinct ones).

The product of its (nonzero) digits is 2211840, while the sum is 54.

The spelling of 6840805116861 in words is "six trillion, eight hundred forty billion, eight hundred five million, one hundred sixteen thousand, eight hundred sixty-one".