99909900991000 has 32 divisors (see below), whose sum is σ = 233789168321280. Its totient is φ = 39963960396000.

The previous prime is 99909900990953. The next prime is 99909900991001. The reversal of 99909900991000 is 19900990999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99909900991001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49954949496 + ... + 49954951495.

It is an arithmetic number, because the mean of its divisors is an integer number (7305911510040).

Almost surely, 2^{99909900991000} is an apocalyptic number.

It is an amenable number.

99909900991000 is an abundant number, since it is smaller than the sum of its proper divisors (133879267330280).

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

99909900991000 is a wasteful number, since it uses less digits than its factorization.

99909900991000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99909901012 (or 99909900998 counting only the distinct ones).

The product of its (nonzero) digits is 4782969, while the sum is 64.

The spelling of 99909900991000 in words is "ninety-nine trillion, nine hundred nine billion, nine hundred million, nine hundred ninety-one thousand".