138709999 has 2 divisors, whose sum is σ = 138710000. Its totient is φ = 138709998.

The previous prime is 138709993. The next prime is 138710029. The reversal of 138709999 is 999907831.

138709999 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 138709999 - 2¹⁷ = 138578927 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138709993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69354999 + 69355000.

It is an arithmetic number, because the mean of its divisors is an integer number (69355000).

Almost surely, 2^138709999 is an apocalyptic number.

138709999 is a deficient number, since it is larger than the sum of its proper divisors (1).

138709999 is an equidigital number, since it uses as much as digits as its factorization.

138709999 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1102248, while the sum is 55.

The square root of 138709999 is about 11777.5209191069. The cubic root of 138709999 is about 517.6496478072.

The spelling of 138709999 in words is "one hundred thirty-eight million, seven hundred nine thousand, nine hundred ninety-nine".