643710580 has 12 divisors (see below), whose sum is σ = 1351792260. Its totient is φ = 257484224.

The previous prime is 643710577. The next prime is 643710581. The reversal of 643710580 is 85017346.

It can be written as a sum of positive squares in 2 ways, for example, as 278289124 + 365421456 = 16682^2 + 19116^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643710581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16092745 + ... + 16092784.

It is an arithmetic number, because the mean of its divisors is an integer number (112649355).

Almost surely, 2^643710580 is an apocalyptic number.

It is an amenable number.

643710580 is an abundant number, since it is smaller than the sum of its proper divisors (708081680).

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

643710580 is a wasteful number, since it uses less digits than its factorization.

643710580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32185538 (or 32185536 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 34.

The square root of 643710580 is about 25371.4520672349. The cubic root of 643710580 is about 863.4361264915.

The spelling of 643710580 in words is "six hundred forty-three million, seven hundred ten thousand, five hundred eighty".