639422521189 has 2 divisors, whose sum is σ = 639422521190. Its totient is φ = 639422521188.

The previous prime is 639422521069. The next prime is 639422521217. The reversal of 639422521189 is 981125224936.

It is a happy number.

639422521189 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 406065896289 + 233356624900 = 637233^2 + 483070^2 .

It is a cyclic number.

It is not a de Polignac number, because 639422521189 - 2⁷ = 639422521061 is a prime.

It is a super-2 number, since 2×639422521189² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (639422528189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319711260594 + 319711260595.

It is an arithmetic number, because the mean of its divisors is an integer number (319711260595).

Almost surely, 2^639422521189 is an apocalyptic number.

It is an amenable number.

639422521189 is a deficient number, since it is larger than the sum of its proper divisors (1).

639422521189 is an equidigital number, since it uses as much as digits as its factorization.

639422521189 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1866240, while the sum is 52.

It can be divided in two parts, 639422 and 521189, that added together give a palindrome (1160611).

The spelling of 639422521189 in words is "six hundred thirty-nine billion, four hundred twenty-two million, five hundred twenty-one thousand, one hundred eighty-nine".