991071042000 has 320 divisors, whose sum is σ = 3444523869696. Its totient is φ = 243706060800.

The previous prime is 991071041927. The next prime is 991071042077. The reversal of 991071042000 is 240170199.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 82908024 + ... + 82919976.

Almost surely, 2^991071042000 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 991071042000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1722261934848).

991071042000 is an abundant number, since it is smaller than the sum of its proper divisors (2453452827696).

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

991071042000 is a wasteful number, since it uses less digits than its factorization.

991071042000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13055 (or 13039 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 33.

The spelling of 991071042000 in words is "nine hundred ninety-one billion, seventy-one million, forty-two thousand".