643402320000 has 1280 divisors, whose sum is σ = 2496160972800. Its totient is φ = 145152000000.

The previous prime is 643402319983. The next prime is 643402320007. The reversal of 643402320000 is 23204346.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (643402320007) by changing a digit.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 5066159937 + ... + 5066160063.

It is an arithmetic number, because the mean of its divisors is an integer number (1950125760).

Almost surely, 2^643402320000 is an apocalyptic number.

643402320000 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 643402320000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1248080486400).

643402320000 is an abundant number, since it is smaller than the sum of its proper divisors (1852758652800).

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

643402320000 is a wasteful number, since it uses less digits than its factorization.

643402320000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 295 (or 268 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 24.

Adding to 643402320000 its reverse (23204346), we get a palindrome (643425524346).

The spelling of 643402320000 in words is "six hundred forty-three billion, four hundred two million, three hundred twenty thousand".