999099991000 has 32 divisors (see below), whose sum is σ = 2337893981280. Its totient is φ = 399639996000.

The previous prime is 999099990961. The next prime is 999099991049. The reversal of 999099991000 is 199990999.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 499548996 + ... + 499550995.

It is an arithmetic number, because the mean of its divisors is an integer number (73059186915).

Almost surely, 2^999099991000 is an apocalyptic number.

It is an amenable number.

999099991000 is an abundant number, since it is smaller than the sum of its proper divisors (1338793990280).

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

999099991000 is a wasteful number, since it uses less digits than its factorization.

999099991000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 999100012 (or 999099998 counting only the distinct ones).

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

The spelling of 999099991000 in words is "nine hundred ninety-nine billion, ninety-nine million, nine hundred ninety-one thousand".