639573097 has 2 divisors, whose sum is σ = 639573098. Its totient is φ = 639573096.

The previous prime is 639573071. The next prime is 639573149. The reversal of 639573097 is 790375936.

639573097 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., 536570896 + 103002201 = 23164^2 + 10149^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-639573097 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 639573097.

It is not a weakly prime, because it can be changed into another prime (639573007) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319786548 + 319786549.

It is an arithmetic number, because the mean of its divisors is an integer number (319786549).

Almost surely, 2^639573097 is an apocalyptic number.

It is an amenable number.

639573097 is a deficient number, since it is larger than the sum of its proper divisors (1).

639573097 is an equidigital number, since it uses as much as digits as its factorization.

639573097 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1071630, while the sum is 49.

The square root of 639573097 is about 25289.7824624887. The cubic root of 639573097 is about 861.5822220113.

The spelling of 639573097 in words is "six hundred thirty-nine million, five hundred seventy-three thousand, ninety-seven".