1991916990480 has 320 divisors, whose sum is σ = 6400904601600. Its totient is φ = 512197969920.

The previous prime is 1991916990419. The next prime is 1991916990493. The reversal of 1991916990480 is 840996191991.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 144032206 + ... + 144046034.

It is an arithmetic number, because the mean of its divisors is an integer number (20002826880).

Almost surely, 2^{1991916990480} is an apocalyptic number.

1991916990480 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1991916990480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3200452300800).

1991916990480 is an abundant number, since it is smaller than the sum of its proper divisors (4408987611120).

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

1991916990480 is a wasteful number, since it uses less digits than its factorization.

1991916990480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14102 (or 14096 counting only the distinct ones).

The product of its (nonzero) digits is 11337408, while the sum is 66.

The spelling of 1991916990480 in words is "one trillion, nine hundred ninety-one billion, nine hundred sixteen million, nine hundred ninety thousand, four hundred eighty".