9808541861 has 2 divisors, whose sum is σ = 9808541862. Its totient is φ = 9808541860.

The previous prime is 9808541839. The next prime is 9808541863. The reversal of 9808541861 is 1681458089.

9808541861 = 70030² + 70031².

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4904340961 + 4904200900 = 70031^2 + 70030^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9808541861 is a prime.

It is a Sophie Germain prime.

Together with 9808541863, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9808541863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4904270930 + 4904270931.

It is an arithmetic number, because the mean of its divisors is an integer number (4904270931).

Almost surely, 2^9808541861 is an apocalyptic number.

9808541861 is the 70031-st centered square number.

It is an amenable number.

9808541861 is a deficient number, since it is larger than the sum of its proper divisors (1).

9808541861 is an equidigital number, since it uses as much as digits as its factorization.

9808541861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 552960, while the sum is 50.

The square root of 9808541861 is about 99038.0828822933. The cubic root of 9808541861 is about 2140.5965278088.

The spelling of 9808541861 in words is "nine billion, eight hundred eight million, five hundred forty-one thousand, eight hundred sixty-one".