138908064779 has 8 divisors (see below), whose sum is σ = 151550902272. Its totient is φ = 126267699240.

The previous prime is 138908064769. The next prime is 138908064781. The reversal of 138908064779 is 977460809831.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138908064779 is a prime.

It is not an unprimeable number, because it can be changed into a prime (138908064709) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 499499 + ... + 726164.

It is an arithmetic number, because the mean of its divisors is an integer number (18943862784).

Almost surely, 2^138908064779 is an apocalyptic number.

138908064779 is a deficient number, since it is larger than the sum of its proper divisors (12642837493).

138908064779 is a wasteful number, since it uses less digits than its factorization.

138908064779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1235977.

The product of its (nonzero) digits is 18289152, while the sum is 62.

The spelling of 138908064779 in words is "one hundred thirty-eight billion, nine hundred eight million, sixty-four thousand, seven hundred seventy-nine".