138839369 has 2 divisors, whose sum is σ = 138839370. Its totient is φ = 138839368.

The previous prime is 138839333. The next prime is 138839387. The reversal of 138839369 is 963938831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 138180025 + 659344 = 11755^2 + 812^2 .

It is a cyclic number.

It is not a de Polignac number, because 138839369 - 2²⁴ = 122062153 is a prime.

It is a super-2 number, since 2×138839369² = 38552740768636322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (138839399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69419684 + 69419685.

It is an arithmetic number, because the mean of its divisors is an integer number (69419685).

Almost surely, 2^138839369 is an apocalyptic number.

It is an amenable number.

138839369 is a deficient number, since it is larger than the sum of its proper divisors (1).

138839369 is an equidigital number, since it uses as much as digits as its factorization.

138839369 is an evil number, because the sum of its binary digits is even.

The product of its digits is 839808, while the sum is 50.

The square root of 138839369 is about 11783.0118815182. The cubic root of 138839369 is about 517.8105290860.

The spelling of 138839369 in words is "one hundred thirty-eight million, eight hundred thirty-nine thousand, three hundred sixty-nine".