3847981861 has 2 divisors, whose sum is σ = 3847981862. Its totient is φ = 3847981860.

The previous prime is 3847981853. The next prime is 3847981871. The reversal of 3847981861 is 1681897483.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3847844961 + 136900 = 62031^2 + 370^2 .

It is a cyclic number.

It is not a de Polignac number, because 3847981861 - 2³ = 3847981853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3847981871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1923990930 + 1923990931.

It is an arithmetic number, because the mean of its divisors is an integer number (1923990931).

Almost surely, 2^3847981861 is an apocalyptic number.

It is an amenable number.

3847981861 is a deficient number, since it is larger than the sum of its proper divisors (1).

3847981861 is an equidigital number, since it uses as much as digits as its factorization.

3847981861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2322432, while the sum is 55.

The square root of 3847981861 is about 62032.1034707030. The cubic root of 3847981861 is about 1567.0313031191.

The spelling of 3847981861 in words is "three billion, eight hundred forty-seven million, nine hundred eighty-one thousand, eight hundred sixty-one".