138728168640 has 560 divisors, whose sum is σ = 531614603520. Its totient is φ = 34226841600.

The previous prime is 138728168639. The next prime is 138728168647. The reversal of 138728168640 is 46861827831.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (138728168647) 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 79 ways as a sum of consecutive naturals, for example, 21173365 + ... + 21179915.

It is an arithmetic number, because the mean of its divisors is an integer number (949311792).

Almost surely, 2^138728168640 is an apocalyptic number.

138728168640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138728168640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (265807301760).

138728168640 is an abundant number, since it is smaller than the sum of its proper divisors (392886434880).

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

138728168640 is a wasteful number, since it uses less digits than its factorization.

138728168640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6642 (or 6623 counting only the distinct ones).

The product of its (nonzero) digits is 3096576, while the sum is 54.

The spelling of 138728168640 in words is "one hundred thirty-eight billion, seven hundred twenty-eight million, one hundred sixty-eight thousand, six hundred forty".