138045917 has 2 divisors, whose sum is σ = 138045918. Its totient is φ = 138045916.

The previous prime is 138045881. The next prime is 138045923. The reversal of 138045917 is 719540831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 107453956 + 30591961 = 10366^2 + 5531^2 .

It is an emirp because it is prime and its reverse (719540831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 138045917 - 2¹⁸ = 137783773 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138045217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69022958 + 69022959.

It is an arithmetic number, because the mean of its divisors is an integer number (69022959).

Almost surely, 2^138045917 is an apocalyptic number.

It is an amenable number.

138045917 is a deficient number, since it is larger than the sum of its proper divisors (1).

138045917 is an equidigital number, since it uses as much as digits as its factorization.

138045917 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 30240, while the sum is 38.

The square root of 138045917 is about 11749.2943192347. The cubic root of 138045917 is about 516.8222336031.

The spelling of 138045917 in words is "one hundred thirty-eight million, forty-five thousand, nine hundred seventeen".