639464717 has 2 divisors, whose sum is σ = 639464718. Its totient is φ = 639464716.

The previous prime is 639464711. The next prime is 639464731. The reversal of 639464717 is 717464936.

It is a happy number.

639464717 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 633579241 + 5885476 = 25171^2 + 2426^2 .

It is a cyclic number.

It is not a de Polignac number, because 639464717 - 2⁸ = 639464461 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (639464711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319732358 + 319732359.

It is an arithmetic number, because the mean of its divisors is an integer number (319732359).

Almost surely, 2^639464717 is an apocalyptic number.

It is an amenable number.

639464717 is a deficient number, since it is larger than the sum of its proper divisors (1).

639464717 is an equidigital number, since it uses as much as digits as its factorization.

639464717 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 762048, while the sum is 47.

The square root of 639464717 is about 25287.6396091055. The cubic root of 639464717 is about 861.5335522780.

The spelling of 639464717 in words is "six hundred thirty-nine million, four hundred sixty-four thousand, seven hundred seventeen".