3869809861 has 4 divisors (see below), whose sum is σ = 3870133452. Its totient is φ = 3869486272.

The previous prime is 3869809753. The next prime is 3869809871. The reversal of 3869809861 is 1689089683.

3869809861 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1689089683 = 19 ⋅88899457.

It can be written as a sum of positive squares in 2 ways, for example, as 509404900 + 3360404961 = 22570^2 + 57969^2 .

It is a cyclic number.

It is not a de Polignac number, because 3869809861 - 2¹³ = 3869801669 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 3869809796 and 3869809805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3869809871) 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, 143140 + ... + 168013.

It is an arithmetic number, because the mean of its divisors is an integer number (967533363).

Almost surely, 2^3869809861 is an apocalyptic number.

It is an amenable number.

3869809861 is a deficient number, since it is larger than the sum of its proper divisors (323591).

3869809861 is a wasteful number, since it uses less digits than its factorization.

3869809861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 323590.

The product of its (nonzero) digits is 4478976, while the sum is 58.

The square root of 3869809861 is about 62207.7958217457. The cubic root of 3869809861 is about 1569.9887568670.

The spelling of 3869809861 in words is "three billion, eight hundred sixty-nine million, eight hundred nine thousand, eight hundred sixty-one".