9999867949 has 2 divisors, whose sum is σ = 9999867950. Its totient is φ = 9999867948.

The previous prime is 9999867923. The next prime is 9999868009. The reversal of 9999867949 is 9497689999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8334411849 + 1665456100 = 91293^2 + 40810^2 .

It is a cyclic number.

It is not a de Polignac number, because 9999867949 - 2³¹ = 7852384301 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9999862949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4999933974 + 4999933975.

It is an arithmetic number, because the mean of its divisors is an integer number (4999933975).

Almost surely, 2^9999867949 is an apocalyptic number.

It is an amenable number.

9999867949 is a deficient number, since it is larger than the sum of its proper divisors (1).

9999867949 is an equidigital number, since it uses as much as digits as its factorization.

9999867949 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 714256704, while the sum is 79.

The square root of 9999867949 is about 99999.3397428203. The cubic root of 9999867949 is about 2154.4252068150.

The spelling of 9999867949 in words is "nine billion, nine hundred ninety-nine million, eight hundred sixty-seven thousand, nine hundred forty-nine".