138505459680 has 768 divisors, whose sum is σ = 571405363200. Its totient is φ = 30680432640.

The previous prime is 138505459649. The next prime is 138505459681. The reversal of 138505459680 is 86954505831.

138505459680 is a `hidden beast` number, since 1 + 3 + 8 + 5 + 0 + 545 + 96 + 8 + 0 = 666.

It is a super-2 number, since 2×138505459680² (a number of 23 digits) contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138505459681) 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, 142641595 + ... + 142642565.

It is an arithmetic number, because the mean of its divisors is an integer number (744017400).

Almost surely, 2^138505459680 is an apocalyptic number.

138505459680 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 138505459680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (285702681600).

138505459680 is an abundant number, since it is smaller than the sum of its proper divisors (432899903520).

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

138505459680 is a wasteful number, since it uses less digits than its factorization.

138505459680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1144 (or 1130 counting only the distinct ones).

The product of its (nonzero) digits is 5184000, while the sum is 54.

The spelling of 138505459680 in words is "one hundred thirty-eight billion, five hundred five million, four hundred fifty-nine thousand, six hundred eighty".