639729321727 has 8 divisors (see below), whose sum is σ = 648753998112. Its totient is φ = 630705045600.

The previous prime is 639729321691. The next prime is 639729321731. The reversal of 639729321727 is 727123927936.

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 639729321727 - 2¹⁹ = 639728797439 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639729324727) 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, 4796077 + ... + 4927657.

It is an arithmetic number, because the mean of its divisors is an integer number (81094249764).

Almost surely, 2^639729321727 is an apocalyptic number.

639729321727 is a deficient number, since it is larger than the sum of its proper divisors (9024676385).

639729321727 is a wasteful number, since it uses less digits than its factorization.

639729321727 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200129.

The product of its digits is 12002256, while the sum is 58.

The spelling of 639729321727 in words is "six hundred thirty-nine billion, seven hundred twenty-nine million, three hundred twenty-one thousand, seven hundred twenty-seven".