138961681344 has 168 divisors, whose sum is σ = 409106309040. Its totient is φ = 45072986112.

The previous prime is 138961681343. The next prime is 138961681381. The reversal of 138961681344 is 443186169831.

138961681344 is a `hidden beast` number, since 1 + 3 + 8 + 9 + 616 + 8 + 13 + 4 + 4 = 666.

138961681344 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138961681343) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6652164 + ... + 6673020.

Almost surely, 2^138961681344 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138961681344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (204553154520).

138961681344 is an abundant number, since it is smaller than the sum of its proper divisors (270144627696).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

138961681344 is a wasteful number, since it uses less digits than its factorization.

138961681344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21187 (or 21174 counting only the distinct ones).

The product of its digits is 2985984, while the sum is 54.

The spelling of 138961681344 in words is "one hundred thirty-eight billion, nine hundred sixty-one million, six hundred eighty-one thousand, three hundred forty-four".