9941843981 has 2 divisors, whose sum is σ = 9941843982. Its totient is φ = 9941843980.

The previous prime is 9941843929. The next prime is 9941844013. The reversal of 9941843981 is 1893481499.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9789321481 + 152522500 = 98941^2 + 12350^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9941843981 is a prime.

It is a super-2 number, since 2×9941843981² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9941843921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4970921990 + 4970921991.

It is an arithmetic number, because the mean of its divisors is an integer number (4970921991).

Almost surely, 2^9941843981 is an apocalyptic number.

It is an amenable number.

9941843981 is a deficient number, since it is larger than the sum of its proper divisors (1).

9941843981 is an equidigital number, since it uses as much as digits as its factorization.

9941843981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2239488, while the sum is 56.

The square root of 9941843981 is about 99708.7959058778. The cubic root of 9941843981 is about 2150.2501227664.

The spelling of 9941843981 in words is "nine billion, nine hundred forty-one million, eight hundred forty-three thousand, nine hundred eighty-one".