638615547413 has 2 divisors, whose sum is σ = 638615547414. Its totient is φ = 638615547412.

The previous prime is 638615547407. The next prime is 638615547439. The reversal of 638615547413 is 314745516836.

638615547413 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., 498602629924 + 140012917489 = 706118^2 + 374183^2 .

It is a cyclic number.

It is not a de Polignac number, because 638615547413 - 2¹⁰ = 638615546389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (638615547473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319307773706 + 319307773707.

It is an arithmetic number, because the mean of its divisors is an integer number (319307773707).

Almost surely, 2^638615547413 is an apocalyptic number.

It is an amenable number.

638615547413 is a deficient number, since it is larger than the sum of its proper divisors (1).

638615547413 is an equidigital number, since it uses as much as digits as its factorization.

638615547413 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7257600, while the sum is 53.

The spelling of 638615547413 in words is "six hundred thirty-eight billion, six hundred fifteen million, five hundred forty-seven thousand, four hundred thirteen".