643934480 has 160 divisors (see below), whose sum is σ = 1804646400. Its totient is φ = 213373440.

The previous prime is 643934477. The next prime is 643934497. The reversal of 643934480 is 84439346.

643934480 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×643934480² = 829303229065740800, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 850262 + ... + 851018.

It is an arithmetic number, because the mean of its divisors is an integer number (11279040).

Almost surely, 2^643934480 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 643934480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (902323200).

643934480 is an abundant number, since it is smaller than the sum of its proper divisors (1160711920).

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

643934480 is a wasteful number, since it uses less digits than its factorization.

643934480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 822 (or 802 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 41.

The square root of 643934480 is about 25375.8641232176. The cubic root of 643934480 is about 863.5362237219.

The spelling of 643934480 in words is "six hundred forty-three million, nine hundred thirty-four thousand, four hundred eighty".