643731825439 has 8 divisors (see below), whose sum is σ = 682596363600. Its totient is φ = 604978171776.

The previous prime is 643731825433. The next prime is 643731825449. The reversal of 643731825439 is 934528137346.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 643731825439 - 2⁷ = 643731825311 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 643731825439.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643731825433) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27709164 + ... + 27732385.

It is an arithmetic number, because the mean of its divisors is an integer number (85324545450).

Almost surely, 2^643731825439 is an apocalyptic number.

643731825439 is a deficient number, since it is larger than the sum of its proper divisors (38864538161).

643731825439 is a wasteful number, since it uses less digits than its factorization.

643731825439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55442249.

The product of its digits is 13063680, while the sum is 55.

The spelling of 643731825439 in words is "six hundred forty-three billion, seven hundred thirty-one million, eight hundred twenty-five thousand, four hundred thirty-nine".