138640899539 has 2 divisors, whose sum is σ = 138640899540. Its totient is φ = 138640899538.

The previous prime is 138640899503. The next prime is 138640899557. The reversal of 138640899539 is 935998046831.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 138640899539 - 2⁸ = 138640899283 is a prime.

It is not a weakly prime, because it can be changed into another prime (138640893539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69320449769 + 69320449770.

It is an arithmetic number, because the mean of its divisors is an integer number (69320449770).

Almost surely, 2^138640899539 is an apocalyptic number.

138640899539 is a deficient number, since it is larger than the sum of its proper divisors (1).

138640899539 is an equidigital number, since it uses as much as digits as its factorization.

138640899539 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 50388480, while the sum is 65.

The spelling of 138640899539 in words is "one hundred thirty-eight billion, six hundred forty million, eight hundred ninety-nine thousand, five hundred thirty-nine".