639389785653 has 12 divisors (see below), whose sum is σ = 923620059180. Its totient is φ = 426233533056.

The previous prime is 639389785621. The next prime is 639389785693. The reversal of 639389785653 is 356587983936.

It can be written as a sum of positive squares in 2 ways, for example, as 237279074769 + 402110710884 = 487113^2 + 634122^2 .

It is not a de Polignac number, because 639389785653 - 2⁵ = 639389785621 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639389785693) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2039268 + ... + 2331821.

It is an arithmetic number, because the mean of its divisors is an integer number (76968338265).

Almost surely, 2^639389785653 is an apocalyptic number.

It is an amenable number.

639389785653 is a deficient number, since it is larger than the sum of its proper divisors (284230273527).

639389785653 is a wasteful number, since it uses less digits than its factorization.

639389785653 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4387348 (or 4387345 counting only the distinct ones).

The product of its digits is 881798400, while the sum is 72.

The spelling of 639389785653 in words is "six hundred thirty-nine billion, three hundred eighty-nine million, seven hundred eighty-five thousand, six hundred fifty-three".