999729989 has 2 divisors, whose sum is σ = 999729990. Its totient is φ = 999729988.

The previous prime is 999729977. The next prime is 999730093. The reversal of 999729989 is 989927999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 758176225 + 241553764 = 27535^2 + 15542^2 .

It is an emirp because it is prime and its reverse (989927999) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 999729989 - 2⁸ = 999729733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999729959) 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, 499864994 + 499864995.

It is an arithmetic number, because the mean of its divisors is an integer number (499864995).

Almost surely, 2^999729989 is an apocalyptic number.

It is an amenable number.

999729989 is a deficient number, since it is larger than the sum of its proper divisors (1).

999729989 is an equidigital number, since it uses as much as digits as its factorization.

999729989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 59521392, while the sum is 71.

The square root of 999729989 is about 31618.5070646923. The cubic root of 999729989 is about 999.9099882315.

The spelling of 999729989 in words is "nine hundred ninety-nine million, seven hundred twenty-nine thousand, nine hundred eighty-nine".