999599999 has 2 divisors, whose sum is σ = 999600000. Its totient is φ = 999599998.

The previous prime is 999599989. The next prime is 999600037. The reversal of 999599999 is 999995999.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 999599999 - 2²⁴ = 982822783 is a prime.

999599999 is a modest number, since divided by 99999 gives 9995 as remainder.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999599969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499799999 + 499800000.

It is an arithmetic number, because the mean of its divisors is an integer number (499800000).

Almost surely, 2^999599999 is an apocalyptic number.

999599999 is a deficient number, since it is larger than the sum of its proper divisors (1).

999599999 is an equidigital number, since it uses as much as digits as its factorization.

999599999 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 215233605, while the sum is 77.

The square root of 999599999 is about 31616.4513979669. The cubic root of 999599999 is about 999.8666485515.

The spelling of 999599999 in words is "nine hundred ninety-nine million, five hundred ninety-nine thousand, nine hundred ninety-nine".