643662088640 has 56 divisors (see below), whose sum is σ = 1532861096832. Its totient is φ = 257441192960.

The previous prime is 643662088639. The next prime is 643662088649. The reversal of 643662088640 is 46880266346.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643662088649) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3632177 + ... + 3805263.

Almost surely, 2^643662088640 is an apocalyptic number.

It is an amenable number.

643662088640 is an abundant number, since it is smaller than the sum of its proper divisors (889199008192).

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

643662088640 is a wasteful number, since it uses less digits than its factorization.

643662088640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 184725 (or 184715 counting only the distinct ones).

The product of its (nonzero) digits is 7962624, while the sum is 53.

The spelling of 643662088640 in words is "six hundred forty-three billion, six hundred sixty-two million, eighty-eight thousand, six hundred forty".