643800568320 has 1920 divisors, whose sum is σ = 2898853461504. Its totient is φ = 128421199872.

The previous prime is 643800568309. The next prime is 643800568331. The reversal of 643800568320 is 23865008346.

It is a happy number.

643800568320 is a `hidden beast` number, since 6 + 4 + 3 + 80 + 0 + 568 + 3 + 2 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (643800568309) and next prime (643800568331).

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

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 3335754144 + ... + 3335754336.

Almost surely, 2^643800568320 is an apocalyptic number.

643800568320 is a gapful number since it is divisible by the number (60) 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 643800568320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1449426730752).

643800568320 is an abundant number, since it is smaller than the sum of its proper divisors (2255052893184).

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

643800568320 is a wasteful number, since it uses less digits than its factorization.

643800568320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 322 (or 303 counting only the distinct ones).

The product of its (nonzero) digits is 829440, while the sum is 45.

The spelling of 643800568320 in words is "six hundred forty-three billion, eight hundred million, five hundred sixty-eight thousand, three hundred twenty".