138942019 has 2 divisors, whose sum is σ = 138942020. Its totient is φ = 138942018.

The previous prime is 138941983. The next prime is 138942047. The reversal of 138942019 is 910249831.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 138942019 - 2⁹ = 138941507 is a prime.

It is a super-2 number, since 2×138942019² = 38609769287592722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (138942719) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69471009 + 69471010.

It is an arithmetic number, because the mean of its divisors is an integer number (69471010).

Almost surely, 2^138942019 is an apocalyptic number.

138942019 is a deficient number, since it is larger than the sum of its proper divisors (1).

138942019 is an equidigital number, since it uses as much as digits as its factorization.

138942019 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 138942019 is about 11787.3669239572. The cubic root of 138942019 is about 517.9381109505.

The spelling of 138942019 in words is "one hundred thirty-eight million, nine hundred forty-two thousand, nineteen".