9891131 has 2 divisors, whose sum is σ = 9891132. Its totient is φ = 9891130.

The previous prime is 9891121. The next prime is 9891137. The reversal of 9891131 is 1311989.

9891131 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9891131 is a prime.

It is a super-2 number, since 2×9891131² = 195668944918322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (9891137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4945565 + 4945566.

It is an arithmetic number, because the mean of its divisors is an integer number (4945566).

Almost surely, 2^9891131 is an apocalyptic number.

9891131 is a deficient number, since it is larger than the sum of its proper divisors (1).

9891131 is an equidigital number, since it uses as much as digits as its factorization.

9891131 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1944, while the sum is 32.

The square root of 9891131 is about 3145.0168521011. The cubic root of 9891131 is about 214.6587772885.

The spelling of 9891131 in words is "nine million, eight hundred ninety-one thousand, one hundred thirty-one".