9999998731 has 2 divisors, whose sum is σ = 9999998732. Its totient is φ = 9999998730.

The previous prime is 9999998711. The next prime is 9999998783. The reversal of 9999998731 is 1378999999.

9999998731 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9999998731 is a prime.

It is a super-2 number, since 2×9999998731² (a number of 21 digits) contains 22 as substring.

It is a nialpdrome in base 10.

It is not a weakly prime, because it can be changed into another prime (9999998711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4999999365 + 4999999366.

It is an arithmetic number, because the mean of its divisors is an integer number (4999999366).

Almost surely, 2^9999998731 is an apocalyptic number.

9999998731 is a deficient number, since it is larger than the sum of its proper divisors (1).

9999998731 is an equidigital number, since it uses as much as digits as its factorization.

9999998731 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 89282088, while the sum is 73.

The square root of 9999998731 is about 99999.9936549998. The cubic root of 9999998731 is about 2154.4345988993.

The spelling of 9999998731 in words is "nine billion, nine hundred ninety-nine million, nine hundred ninety-eight thousand, seven hundred thirty-one".