138218579 has 2 divisors, whose sum is σ = 138218580. Its totient is φ = 138218578.

The previous prime is 138218573. The next prime is 138218617. The reversal of 138218579 is 975812831.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 138218579 - 2²⁰ = 137170003 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (138218573) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69109289 + 69109290.

It is an arithmetic number, because the mean of its divisors is an integer number (69109290).

Almost surely, 2^138218579 is an apocalyptic number.

138218579 is a deficient number, since it is larger than the sum of its proper divisors (1).

138218579 is an equidigital number, since it uses as much as digits as its factorization.

138218579 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120960, while the sum is 44.

The square root of 138218579 is about 11756.6397835436. The cubic root of 138218579 is about 517.0376169679.

The spelling of 138218579 in words is "one hundred thirty-eight million, two hundred eighteen thousand, five hundred seventy-nine".