138066689 has 2 divisors, whose sum is σ = 138066690. Its totient is φ = 138066688.

The previous prime is 138066613. The next prime is 138066727. The reversal of 138066689 is 986660831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 130142464 + 7924225 = 11408^2 + 2815^2 .

It is a cyclic number.

It is not a de Polignac number, because 138066689 - 2¹⁶ = 138001153 is a prime.

It is a super-2 number, since 2×138066689² = 38124821222845442, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (138062689) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69033344 + 69033345.

It is an arithmetic number, because the mean of its divisors is an integer number (69033345).

Almost surely, 2^138066689 is an apocalyptic number.

It is an amenable number.

138066689 is a deficient number, since it is larger than the sum of its proper divisors (1).

138066689 is an equidigital number, since it uses as much as digits as its factorization.

138066689 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 138066689 is about 11750.1782539670. The cubic root of 138066689 is about 516.8481546716.

The spelling of 138066689 in words is "one hundred thirty-eight million, sixty-six thousand, six hundred eighty-nine".