9981731 has 2 divisors, whose sum is σ = 9981732. Its totient is φ = 9981730.

The previous prime is 9981691. The next prime is 9981733. The reversal of 9981731 is 1371899.

It is a strong prime.

It is an emirp because it is prime and its reverse (1371899) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9981731 - 2¹⁸ = 9719587 is a prime.

It is a super-2 number, since 2×9981731² = 199269907512722, which contains 22 as substring.

Together with 9981733, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (9981733) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4990865 + 4990866.

It is an arithmetic number, because the mean of its divisors is an integer number (4990866).

Almost surely, 2^9981731 is an apocalyptic number.

9981731 is a deficient number, since it is larger than the sum of its proper divisors (1).

9981731 is an equidigital number, since it uses as much as digits as its factorization.

9981731 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13608, while the sum is 38.

The square root of 9981731 is about 3159.3877571454. The cubic root of 9981731 is about 215.3121911357.

The spelling of 9981731 in words is "nine million, nine hundred eighty-one thousand, seven hundred thirty-one".