991189110000 has 400 divisors, whose sum is σ = 3314128739328. Its totient is φ = 255024000000.

The previous prime is 991189109993. The next prime is 991189110011. The reversal of 991189110000 is 11981199.

It is a tau number, because it is divible by the number of its divisors (400).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 100105050 + ... + 100114950.

Almost surely, 2^991189110000 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 991189110000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1657064369664).

991189110000 is an abundant number, since it is smaller than the sum of its proper divisors (2322939629328).

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

991189110000 is a wasteful number, since it uses less digits than its factorization.

991189110000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10050 (or 10029 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 39.

The spelling of 991189110000 in words is "nine hundred ninety-one billion, one hundred eighty-nine million, one hundred ten thousand".