643084900 has 18 divisors (see below), whose sum is σ = 1395494450. Its totient is φ = 257233920.

The previous prime is 643084861. The next prime is 643084919. The reversal of 643084900 is 9480346.

It can be written as a sum of positive squares in 3 ways, for example, as 215091556 + 427993344 = 14666^2 + 20688^2 .

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 5 ways as a sum of consecutive naturals, for example, 3215325 + ... + 3215524.

Almost surely, 2^643084900 is an apocalyptic number.

It is an amenable number.

643084900 is an abundant number, since it is smaller than the sum of its proper divisors (752409550).

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

643084900 is a wasteful number, since it uses less digits than its factorization.

643084900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6430863 (or 6430856 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 643084900 is about 25359.1186755376. The cubic root of 643084900 is about 863.1562854878.

The spelling of 643084900 in words is "six hundred forty-three million, eighty-four thousand, nine hundred".