138399293 has 2 divisors, whose sum is σ = 138399294. Its totient is φ = 138399292.

The previous prime is 138399269. The next prime is 138399299. The reversal of 138399293 is 392993831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 137405284 + 994009 = 11722^2 + 997^2 .

It is a cyclic number.

It is not a de Polignac number, because 138399293 - 2⁶ = 138399229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138399299) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69199646 + 69199647.

It is an arithmetic number, because the mean of its divisors is an integer number (69199647).

Almost surely, 2^138399293 is an apocalyptic number.

It is an amenable number.

138399293 is a deficient number, since it is larger than the sum of its proper divisors (1).

138399293 is an equidigital number, since it uses as much as digits as its factorization.

138399293 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 314928, while the sum is 47.

The square root of 138399293 is about 11764.3228874424. The cubic root of 138399293 is about 517.2628525939.

It can be divided in two parts, 13839 and 9293, that added together give a palindrome (23132).

The spelling of 138399293 in words is "one hundred thirty-eight million, three hundred ninety-nine thousand, two hundred ninety-three".