138692399 has 2 divisors, whose sum is σ = 138692400. Its totient is φ = 138692398.

The previous prime is 138692377. The next prime is 138692401. The reversal of 138692399 is 993296831.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 138692399 - 2⁸ = 138692143 is a prime.

It is a Sophie Germain prime.

Together with 138692401, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138694399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69346199 + 69346200.

It is an arithmetic number, because the mean of its divisors is an integer number (69346200).

Almost surely, 2^138692399 is an apocalyptic number.

138692399 is a deficient number, since it is larger than the sum of its proper divisors (1).

138692399 is an equidigital number, since it uses as much as digits as its factorization.

138692399 is an evil number, because the sum of its binary digits is even.

The product of its digits is 629856, while the sum is 50.

The square root of 138692399 is about 11776.7737092975. The cubic root of 138692399 is about 517.6277531608.

The spelling of 138692399 in words is "one hundred thirty-eight million, six hundred ninety-two thousand, three hundred ninety-nine".