3806685206861 has 2 divisors, whose sum is σ = 3806685206862. Its totient is φ = 3806685206860.

The previous prime is 3806685206837. The next prime is 3806685206897. The reversal of 3806685206861 is 1686025866083.

3806685206861 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3546513801961 + 260171404900 = 1883219^2 + 510070^2 .

It is a cyclic number.

It is not a de Polignac number, because 3806685206861 - 2¹⁸ = 3806684944717 is a prime.

It is a super-2 number, since 2×3806685206861² (a number of 26 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 3806685206861.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3806685206461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1903342603430 + 1903342603431.

It is an arithmetic number, because the mean of its divisors is an integer number (1903342603431).

Almost surely, 2^{3806685206861} is an apocalyptic number.

It is an amenable number.

3806685206861 is a deficient number, since it is larger than the sum of its proper divisors (1).

3806685206861 is an equidigital number, since it uses as much as digits as its factorization.

3806685206861 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19906560, while the sum is 59.

The spelling of 3806685206861 in words is "three trillion, eight hundred six billion, six hundred eighty-five million, two hundred six thousand, eight hundred sixty-one".