138740647 has 2 divisors, whose sum is σ = 138740648. Its totient is φ = 138740646.

The previous prime is 138740629. The next prime is 138740671. The reversal of 138740647 is 746047831.

It is a weak prime.

It is an emirp because it is prime and its reverse (746047831) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138740647 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138740947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69370323 + 69370324.

It is an arithmetic number, because the mean of its divisors is an integer number (69370324).

Almost surely, 2^138740647 is an apocalyptic number.

138740647 is a deficient number, since it is larger than the sum of its proper divisors (1).

138740647 is an equidigital number, since it uses as much as digits as its factorization.

138740647 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 112896, while the sum is 40.

The square root of 138740647 is about 11778.8219699595. The cubic root of 138740647 is about 517.6877699282.

The spelling of 138740647 in words is "one hundred thirty-eight million, seven hundred forty thousand, six hundred forty-seven".