138209293 has 2 divisors, whose sum is σ = 138209294. Its totient is φ = 138209292.

The previous prime is 138209261. The next prime is 138209297. The reversal of 138209293 is 392902831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 127306089 + 10903204 = 11283^2 + 3302^2 .

It is a cyclic number.

It is not a de Polignac number, because 138209293 - 2⁵ = 138209261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138209297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69104646 + 69104647.

It is an arithmetic number, because the mean of its divisors is an integer number (69104647).

Almost surely, 2^138209293 is an apocalyptic number.

It is an amenable number.

138209293 is a deficient number, since it is larger than the sum of its proper divisors (1).

138209293 is an equidigital number, since it uses as much as digits as its factorization.

138209293 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 37.

The square root of 138209293 is about 11756.2448511419. The cubic root of 138209293 is about 517.0260379196.

The spelling of 138209293 in words is "one hundred thirty-eight million, two hundred nine thousand, two hundred ninety-three".