9909881 has 2 divisors, whose sum is σ = 9909882. Its totient is φ = 9909880.

The previous prime is 9909871. The next prime is 9909901. The reversal of 9909881 is 1889099.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7203856 + 2706025 = 2684^2 + 1645^2 .

It is an emirp because it is prime and its reverse (1889099) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9909881 - 2¹⁴ = 9893497 is a prime.

It is a super-3 number, since 3×9909881³ (a number of 22 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (9909871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4954940 + 4954941.

It is an arithmetic number, because the mean of its divisors is an integer number (4954941).

Almost surely, 2^9909881 is an apocalyptic number.

It is an amenable number.

9909881 is a deficient number, since it is larger than the sum of its proper divisors (1).

9909881 is an equidigital number, since it uses as much as digits as its factorization.

9909881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 46656, while the sum is 44.

The square root of 9909881 is about 3147.9963468848. The cubic root of 9909881 is about 214.7943300893.

The spelling of 9909881 in words is "nine million, nine hundred nine thousand, eight hundred eighty-one".