99909255990 has 64 divisors (see below), whose sum is σ = 243003110400. Its totient is φ = 26285892864.

The previous prime is 99909255989. The next prime is 99909256001. The reversal of 99909255990 is 9955290999.

It is a Smith number, since the sum of its digits (66) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

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 in 31 ways as a sum of consecutive naturals, for example, 1195801 + ... + 1276619.

It is an arithmetic number, because the mean of its divisors is an integer number (3796923600).

Almost surely, 2^99909255990 is an apocalyptic number.

99909255990 is an abundant number, since it is smaller than the sum of its proper divisors (143093854410).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

99909255990 is a wasteful number, since it uses less digits than its factorization.

99909255990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81381.

The product of its (nonzero) digits is 26572050, while the sum is 66.

The spelling of 99909255990 in words is "ninety-nine billion, nine hundred nine million, two hundred fifty-five thousand, nine hundred ninety".