643573560 has 128 divisors (see below), whose sum is σ = 2266283520. Its totient is φ = 143119872.

The previous prime is 643573559. The next prime is 643573583. The reversal of 643573560 is 65375346.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20727 + ... + 41433.

It is an arithmetic number, because the mean of its divisors is an integer number (17705340).

Almost surely, 2^643573560 is an apocalyptic number.

643573560 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 643573560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1133141760).

643573560 is an abundant number, since it is smaller than the sum of its proper divisors (1622709960).

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

643573560 is a wasteful number, since it uses less digits than its factorization.

643573560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20765 (or 20761 counting only the distinct ones).

The product of its (nonzero) digits is 226800, while the sum is 39.

The square root of 643573560 is about 25368.7516444937. The cubic root of 643573560 is about 863.3748585775.

The spelling of 643573560 in words is "six hundred forty-three million, five hundred seventy-three thousand, five hundred sixty".