138661692128 has 24 divisors (see below), whose sum is σ = 273921932088. Its totient is φ = 69094217344.

The previous prime is 138661692121. The next prime is 138661692133. The reversal of 138661692128 is 821296166831.

It is a self number, because there is not a number n which added to its sum of digits gives 138661692128.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138661692121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7385126 + ... + 7403877.

It is an arithmetic number, because the mean of its divisors is an integer number (11413413837).

Almost surely, 2^138661692128 is an apocalyptic number.

It is an amenable number.

138661692128 is a deficient number, since it is larger than the sum of its proper divisors (135260239960).

138661692128 is a wasteful number, since it uses less digits than its factorization.

138661692128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14789306 (or 14789298 counting only the distinct ones).

The product of its digits is 1492992, while the sum is 53.

The spelling of 138661692128 in words is "one hundred thirty-eight billion, six hundred sixty-one million, six hundred ninety-two thousand, one hundred twenty-eight".