99969999 has 4 divisors (see below), whose sum is σ = 133293336. Its totient is φ = 66646664.

The previous prime is 99969949. The next prime is 99970007. The reversal of 99969999 is 99996999.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 99969999 - 2⁸ = 99969743 is a prime.

99969999 is a modest number, since divided by 9999 gives 9996 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99969949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16661664 + ... + 16661669.

It is an arithmetic number, because the mean of its divisors is an integer number (33323334).

Almost surely, 2^99969999 is an apocalyptic number.

99969999 is a deficient number, since it is larger than the sum of its proper divisors (33323337).

99969999 is a wasteful number, since it uses less digits than its factorization.

99969999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33323336.

The product of its digits is 28697814, while the sum is 69.

The square root of 99969999 is about 9998.4998374756. The cubic root of 99969999 is about 464.1124612831.

Subtracting 99969999 from its reverse (99996999), we obtain a cube (27000 = 30³).

The spelling of 99969999 in words is "ninety-nine million, nine hundred sixty-nine thousand, nine hundred ninety-nine".