9638938391 has 2 divisors, whose sum is σ = 9638938392. Its totient is φ = 9638938390.

The previous prime is 9638938373. The next prime is 9638938427. The reversal of 9638938391 is 1938398369.

9638938391 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 is a cyclic number.

It is not a de Polignac number, because 9638938391 - 2⁶ = 9638938327 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 9638938391.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9638938291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4819469195 + 4819469196.

It is an arithmetic number, because the mean of its divisors is an integer number (4819469196).

Almost surely, 2^9638938391 is an apocalyptic number.

9638938391 is a deficient number, since it is larger than the sum of its proper divisors (1).

9638938391 is an equidigital number, since it uses as much as digits as its factorization.

9638938391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7558272, while the sum is 59.

The square root of 9638938391 is about 98178.0952707884. The cubic root of 9638938391 is about 2128.1867492060.

The spelling of 9638938391 in words is "nine billion, six hundred thirty-eight million, nine hundred thirty-eight thousand, three hundred ninety-one".