643826107932672 has 896 divisors, whose sum is σ = 2057666718044160. Its totient is φ = 175261813309440.

The previous prime is 643826107932617. The next prime is 643826107932677. The reversal of 643826107932672 is 276239701628346.

It is a tau number, because it is divible by the number of its divisors (896).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643826107932677) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 43938169698 + ... + 43938184350.

Almost surely, 2^{643826107932672} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 643826107932672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1028833359022080).

643826107932672 is an abundant number, since it is smaller than the sum of its proper divisors (1413840610111488).

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

643826107932672 is a wasteful number, since it uses less digits than its factorization.

643826107932672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14882 (or 14858 counting only the distinct ones).

The product of its (nonzero) digits is 219469824, while the sum is 66.

The spelling of 643826107932672 in words is "six hundred forty-three trillion, eight hundred twenty-six billion, one hundred seven million, nine hundred thirty-two thousand, six hundred seventy-two".