138438169 has 2 divisors, whose sum is σ = 138438170. Its totient is φ = 138438168.

The previous prime is 138438151. The next prime is 138438193. The reversal of 138438169 is 961834831.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 108056025 + 30382144 = 10395^2 + 5512^2 .

It is a cyclic number.

It is not a de Polignac number, because 138438169 - 2¹¹ = 138436121 is a prime.

It is a super-2 number, since 2×138438169² = 38330253272145122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (138438869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69219084 + 69219085.

It is an arithmetic number, because the mean of its divisors is an integer number (69219085).

Almost surely, 2^138438169 is an apocalyptic number.

It is an amenable number.

138438169 is a deficient number, since it is larger than the sum of its proper divisors (1).

138438169 is an equidigital number, since it uses as much as digits as its factorization.

138438169 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 124416, while the sum is 43.

The square root of 138438169 is about 11765.9750552175. The cubic root of 138438169 is about 517.3112806546.

The spelling of 138438169 in words is "one hundred thirty-eight million, four hundred thirty-eight thousand, one hundred sixty-nine".