643680576 has 336 divisors, whose sum is σ = 2404067328. Its totient is φ = 159667200.

The previous prime is 643680551. The next prime is 643680589. The reversal of 643680576 is 675086346.

It is a tau number, because it is divible by the number of its divisors (336).

It is a congruent number.

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 47 ways as a sum of consecutive naturals, for example, 1019781 + ... + 1020411.

Almost surely, 2^643680576 is an apocalyptic number.

643680576 is a gapful number since it is divisible by the number (66) 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 643680576, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1202033664).

643680576 is an abundant number, since it is smaller than the sum of its proper divisors (1760386752).

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

643680576 is a wasteful number, since it uses less digits than its factorization.

643680576 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 690 (or 677 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 45.

The square root of 643680576 is about 25370.8607658471. The cubic root of 643680576 is about 863.4227110732.

The spelling of 643680576 in words is "six hundred forty-three million, six hundred eighty thousand, five hundred seventy-six".