138542279 has 2 divisors, whose sum is σ = 138542280. Its totient is φ = 138542278.

The previous prime is 138542267. The next prime is 138542311. The reversal of 138542279 is 972245831.

138542279 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 138542279 - 2¹⁶ = 138476743 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138542219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69271139 + 69271140.

It is an arithmetic number, because the mean of its divisors is an integer number (69271140).

Almost surely, 2^138542279 is an apocalyptic number.

138542279 is a deficient number, since it is larger than the sum of its proper divisors (1).

138542279 is an equidigital number, since it uses as much as digits as its factorization.

138542279 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120960, while the sum is 41.

The square root of 138542279 is about 11770.3984214639. The cubic root of 138542279 is about 517.4409264564.

The spelling of 138542279 in words is "one hundred thirty-eight million, five hundred forty-two thousand, two hundred seventy-nine".