138640699 has 2 divisors, whose sum is σ = 138640700. Its totient is φ = 138640698.

The previous prime is 138640681. The next prime is 138640709. The reversal of 138640699 is 996046831.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 138640699 - 2⁷ = 138640571 is a prime.

It is not a weakly prime, because it can be changed into another prime (138640669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69320349 + 69320350.

It is an arithmetic number, because the mean of its divisors is an integer number (69320350).

Almost surely, 2^138640699 is an apocalyptic number.

138640699 is a deficient number, since it is larger than the sum of its proper divisors (1).

138640699 is an equidigital number, since it uses as much as digits as its factorization.

138640699 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 279936, while the sum is 46.

The square root of 138640699 is about 11774.5785062566. The cubic root of 138640699 is about 517.5634269229.

The spelling of 138640699 in words is "one hundred thirty-eight million, six hundred forty thousand, six hundred ninety-nine".