139906009 has 2 divisors, whose sum is σ = 139906010. Its totient is φ = 139906008.

The previous prime is 139906003. The next prime is 139906021. The reversal of 139906009 is 900609931.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 113486409 + 26419600 = 10653^2 + 5140^2 .

It is a cyclic number.

It is not a de Polignac number, because 139906009 - 2⁵ = 139905977 is a prime.

It is not a weakly prime, because it can be changed into another prime (139906003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69953004 + 69953005.

It is an arithmetic number, because the mean of its divisors is an integer number (69953005).

Almost surely, 2^139906009 is an apocalyptic number.

It is an amenable number.

139906009 is a deficient number, since it is larger than the sum of its proper divisors (1).

139906009 is an equidigital number, since it uses as much as digits as its factorization.

139906009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13122, while the sum is 37.

The square root of 139906009 is about 11828.1870546589. The cubic root of 139906009 is about 519.1331823344.

The spelling of 139906009 in words is "one hundred thirty-nine million, nine hundred six thousand, nine".