639380213 has 2 divisors, whose sum is σ = 639380214. Its totient is φ = 639380212.

The previous prime is 639380167. The next prime is 639380219. The reversal of 639380213 is 312083936.

639380213 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., 512660164 + 126720049 = 22642^2 + 11257^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-639380213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (639380219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319690106 + 319690107.

It is an arithmetic number, because the mean of its divisors is an integer number (319690107).

Almost surely, 2^639380213 is an apocalyptic number.

It is an amenable number.

639380213 is a deficient number, since it is larger than the sum of its proper divisors (1).

639380213 is an equidigital number, since it uses as much as digits as its factorization.

639380213 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23328, while the sum is 35.

The square root of 639380213 is about 25285.9686980744. The cubic root of 639380213 is about 861.4956006201.

The spelling of 639380213 in words is "six hundred thirty-nine million, three hundred eighty thousand, two hundred thirteen".