639633430913 has 2 divisors, whose sum is σ = 639633430914. Its totient is φ = 639633430912.

The previous prime is 639633430907. The next prime is 639633430951. The reversal of 639633430913 is 319034336936.

639633430913 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., 637429785664 + 2203645249 = 798392^2 + 46943^2 .

It is a cyclic number.

It is not a de Polignac number, because 639633430913 - 2³⁴ = 622453561729 is a prime.

It is not a weakly prime, because it can be changed into another prime (639633430313) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319816715456 + 319816715457.

It is an arithmetic number, because the mean of its divisors is an integer number (319816715457).

Almost surely, 2^639633430913 is an apocalyptic number.

It is an amenable number.

639633430913 is a deficient number, since it is larger than the sum of its proper divisors (1).

639633430913 is an equidigital number, since it uses as much as digits as its factorization.

639633430913 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2834352, while the sum is 50.

The spelling of 639633430913 in words is "six hundred thirty-nine billion, six hundred thirty-three million, four hundred thirty thousand, nine hundred thirteen".