138766009 has 2 divisors, whose sum is σ = 138766010. Its totient is φ = 138766008.

The previous prime is 138765983. The next prime is 138766037. The reversal of 138766009 is 900667831.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 120890025 + 17875984 = 10995^2 + 4228^2 .

It is a cyclic number.

It is not a de Polignac number, because 138766009 - 2⁷ = 138765881 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (138766039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69383004 + 69383005.

It is an arithmetic number, because the mean of its divisors is an integer number (69383005).

Almost surely, 2^138766009 is an apocalyptic number.

It is an amenable number.

138766009 is a deficient number, since it is larger than the sum of its proper divisors (1).

138766009 is an equidigital number, since it uses as much as digits as its factorization.

138766009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 54432, while the sum is 40.

The square root of 138766009 is about 11779.8985139941. The cubic root of 138766009 is about 517.7193127086.

The spelling of 138766009 in words is "one hundred thirty-eight million, seven hundred sixty-six thousand, nine".