991894848000 has 1920 divisors, whose sum is σ = 4191674572800. Its totient is φ = 206696448000.

The previous prime is 991894847987. The next prime is 991894848059. The reversal of 991894848000 is 848498199.

It is a tau number, because it is divible by the number of its divisors (1920).

It is a super-3 number, since 3×991894848000³ (a number of 37 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 5541311911 + ... + 5541312089.

It is an arithmetic number, because the mean of its divisors is an integer number (2183163840).

Almost surely, 2^991894848000 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 991894848000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2095837286400).

991894848000 is an abundant number, since it is smaller than the sum of its proper divisors (3199779724800).

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

991894848000 is a wasteful number, since it uses less digits than its factorization.

991894848000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 279 (or 246 counting only the distinct ones).

The product of its (nonzero) digits is 5971968, while the sum is 60.

The spelling of 991894848000 in words is "nine hundred ninety-one billion, eight hundred ninety-four million, eight hundred forty-eight thousand".