138681916560 has 640 divisors, whose sum is σ = 554364518400. Its totient is φ = 31512084480.

The previous prime is 138681916543. The next prime is 138681916567. The reversal of 138681916560 is 65619186831.

138681916560 is a `hidden beast` number, since 1 + 3 + 8 + 68 + 1 + 9 + 16 + 560 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 138681916497 and 138681916506.

It is not an unprimeable number, because it can be changed into a prime (138681916567) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 43788097 + ... + 43791263.

It is an arithmetic number, because the mean of its divisors is an integer number (866194560).

Almost surely, 2^138681916560 is an apocalyptic number.

138681916560 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 138681916560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (277182259200).

138681916560 is an abundant number, since it is smaller than the sum of its proper divisors (415682601840).

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

138681916560 is a wasteful number, since it uses less digits than its factorization.

138681916560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3316 (or 3304 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 54.

The spelling of 138681916560 in words is "one hundred thirty-eight billion, six hundred eighty-one million, nine hundred sixteen thousand, five hundred sixty".