9855971641 has 2 divisors, whose sum is σ = 9855971642. Its totient is φ = 9855971640.

The previous prime is 9855971633. The next prime is 9855971659. The reversal of 9855971641 is 1461795589.

It is a happy number.

9855971641 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., 9825765625 + 30206016 = 99125^2 + 5496^2 .

It is a cyclic number.

It is not a de Polignac number, because 9855971641 - 2³ = 9855971633 is a prime.

It is not a weakly prime, because it can be changed into another prime (9855971341) 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, 4927985820 + 4927985821.

It is an arithmetic number, because the mean of its divisors is an integer number (4927985821).

Almost surely, 2^9855971641 is an apocalyptic number.

It is an amenable number.

9855971641 is a deficient number, since it is larger than the sum of its proper divisors (1).

9855971641 is an equidigital number, since it uses as much as digits as its factorization.

9855971641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2721600, while the sum is 55.

The square root of 9855971641 is about 99277.2463407401. The cubic root of 9855971641 is about 2144.0413080082.

The spelling of 9855971641 in words is "nine billion, eight hundred fifty-five million, nine hundred seventy-one thousand, six hundred forty-one".