643395984 has 80 divisors (see below), whose sum is σ = 2072248320. Its totient is φ = 167114880.

The previous prime is 643395959. The next prime is 643396007. The reversal of 643395984 is 489593346.

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 15 ways as a sum of consecutive naturals, for example, 83344 + ... + 90735.

It is an arithmetic number, because the mean of its divisors is an integer number (25903104).

Almost surely, 2^643395984 is an apocalyptic number.

It is an amenable number.

643395984 is an abundant number, since it is smaller than the sum of its proper divisors (1428852336).

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

643395984 is a wasteful number, since it uses less digits than its factorization.

643395984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174108 (or 174102 counting only the distinct ones).

The product of its digits is 2799360, while the sum is 51.

The square root of 643395984 is about 25365.2515067365. The cubic root of 643395984 is about 863.2954432801.

The spelling of 643395984 in words is "six hundred forty-three million, three hundred ninety-five thousand, nine hundred eighty-four".