138686069 has 2 divisors, whose sum is σ = 138686070. Its totient is φ = 138686068.

The previous prime is 138686039. The next prime is 138686081. The reversal of 138686069 is 960686831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 71199844 + 67486225 = 8438^2 + 8215^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138686069 is a prime.

It is a super-2 number, since 2×138686069² = 38467651469345522, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138686039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69343034 + 69343035.

It is an arithmetic number, because the mean of its divisors is an integer number (69343035).

Almost surely, 2^138686069 is an apocalyptic number.

It is an amenable number.

138686069 is a deficient number, since it is larger than the sum of its proper divisors (1).

138686069 is an equidigital number, since it uses as much as digits as its factorization.

138686069 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 373248, while the sum is 47.

The square root of 138686069 is about 11776.5049569047. The cubic root of 138686069 is about 517.6198780993.

The spelling of 138686069 in words is "one hundred thirty-eight million, six hundred eighty-six thousand, sixty-nine".