138144779 has 2 divisors, whose sum is σ = 138144780. Its totient is φ = 138144778.

The previous prime is 138144757. The next prime is 138144817. The reversal of 138144779 is 977441831.

138144779 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 138144779 - 2¹² = 138140683 is a prime.

It is not a weakly prime, because it can be changed into another prime (138144679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69072389 + 69072390.

It is an arithmetic number, because the mean of its divisors is an integer number (69072390).

Almost surely, 2^138144779 is an apocalyptic number.

138144779 is a deficient number, since it is larger than the sum of its proper divisors (1).

138144779 is an equidigital number, since it uses as much as digits as its factorization.

138144779 is an evil number, because the sum of its binary digits is even.

The product of its digits is 169344, while the sum is 44.

The square root of 138144779 is about 11753.5007125537. The cubic root of 138144779 is about 516.9455787638.

The spelling of 138144779 in words is "one hundred thirty-eight million, one hundred forty-four thousand, seven hundred seventy-nine".