639047252389 has 20 divisors (see below), whose sum is σ = 802857789356. Its totient is φ = 505619779392.

The previous prime is 639047252369. The next prime is 639047252413. The reversal of 639047252389 is 983252740936.

639047252389 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 56012688900 + 583034563489 = 236670^2 + 763567^2 .

It is not a de Polignac number, because 639047252389 - 2³³ = 630457317797 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639047252369) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 10205664 + ... + 10268089.

Almost surely, 2^639047252389 is an apocalyptic number.

It is an amenable number.

639047252389 is a deficient number, since it is larger than the sum of its proper divisors (163810536967).

639047252389 is an equidigital number, since it uses as much as digits as its factorization.

639047252389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20473794 (or 20473773 counting only the distinct ones).

The product of its (nonzero) digits is 19595520, while the sum is 58.

The spelling of 639047252389 in words is "six hundred thirty-nine billion, forty-seven million, two hundred fifty-two thousand, three hundred eighty-nine".