138579517440 has 1792 divisors, whose sum is σ = 649993559040. Its totient is φ = 27518828544.

The previous prime is 138579517411. The next prime is 138579517451. The reversal of 138579517440 is 44715975831.

138579517440 is a `hidden beast` number, since 1 + 3 + 85 + 7 + 9 + 517 + 4 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (1792).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 8151736312 + ... + 8151736328.

It is an arithmetic number, because the mean of its divisors is an integer number (362719620).

Almost surely, 2^138579517440 is an apocalyptic number.

138579517440 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 138579517440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (324996779520).

138579517440 is an abundant number, since it is smaller than the sum of its proper divisors (511414041600).

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

138579517440 is an frugal number, since it uses more digits than its factorization.

138579517440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89 (or 47 counting only the distinct ones).

The product of its (nonzero) digits is 4233600, while the sum is 54.

The spelling of 138579517440 in words is "one hundred thirty-eight billion, five hundred seventy-nine million, five hundred seventeen thousand, four hundred forty".