9920571841 has 2 divisors, whose sum is σ = 9920571842. Its totient is φ = 9920571840.

The previous prime is 9920571779. The next prime is 9920571883. The reversal of 9920571841 is 1481750299.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9180514225 + 740057616 = 95815^2 + 27204^2 .

It is an emirp because it is prime and its reverse (1481750299) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9920571841 - 2²⁵ = 9887017409 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 9920571791 and 9920571800.

It is not a weakly prime, because it can be changed into another prime (9920572841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4960285920 + 4960285921.

It is an arithmetic number, because the mean of its divisors is an integer number (4960285921).

Almost surely, 2^9920571841 is an apocalyptic number.

It is an amenable number.

9920571841 is a deficient number, since it is larger than the sum of its proper divisors (1).

9920571841 is an equidigital number, since it uses as much as digits as its factorization.

9920571841 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 181440, while the sum is 46.

The square root of 9920571841 is about 99602.0674534419. The cubic root of 9920571841 is about 2148.7154281460.

The spelling of 9920571841 in words is "nine billion, nine hundred twenty million, five hundred seventy-one thousand, eight hundred forty-one".