1643811832320 has 640 divisors, whose sum is σ = 6244652316672. Its totient is φ = 361060761600.

The previous prime is 1643811832319. The next prime is 1643811832343. The reversal of 1643811832320 is 232381183461.

It is a tau number, because it is divible by the number of its divisors (640).

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (42).

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, 147673155 + ... + 147684285.

Almost surely, 2^{1643811832320} is an apocalyptic number.

1643811832320 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 1643811832320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3122326158336).

1643811832320 is an abundant number, since it is smaller than the sum of its proper divisors (4600840484352).

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

1643811832320 is a wasteful number, since it uses less digits than its factorization.

1643811832320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11272 (or 11256 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 42.

The spelling of 1643811832320 in words is "one trillion, six hundred forty-three billion, eight hundred eleven million, eight hundred thirty-two thousand, three hundred twenty".