3991446328320 has 528 divisors, whose sum is σ = 15300192435840. Its totient is φ = 953986252800.

The previous prime is 3991446328253. The next prime is 3991446328379. The reversal of 3991446328320 is 238236441993.

3991446328320 is a `hidden beast` number, since 3 + 9 + 91 + 446 + 32 + 83 + 2 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (528).

It is a congruent number.

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 47 ways as a sum of consecutive naturals, for example, 35933026 + ... + 36043934.

Almost surely, 2^{3991446328320} is an apocalyptic number.

3991446328320 is a gapful number since it is divisible by the number (30) 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 3991446328320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7650096217920).

3991446328320 is an abundant number, since it is smaller than the sum of its proper divisors (11308746107520).

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

3991446328320 is a wasteful number, since it uses less digits than its factorization.

3991446328320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111022 (or 111001 counting only the distinct ones).

The product of its (nonzero) digits is 6718464, while the sum is 54.

The spelling of 3991446328320 in words is "three trillion, nine hundred ninety-one billion, four hundred forty-six million, three hundred twenty-eight thousand, three hundred twenty".