138239555279544 has 256 divisors, whose sum is σ = 401109276672000. Its totient is φ = 44058841505280.

The previous prime is 138239555279537. The next prime is 138239555279611. The reversal of 138239555279544 is 445972555932831.

138239555279544 is a `hidden beast` number, since 1 + 3 + 8 + 2 + 3 + 9 + 5 + 5 + 5 + 2 + 79 + 544 = 666.

It is a super-2 number, since 2×138239555279544² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 430220047 + ... + 430541249.

It is an arithmetic number, because the mean of its divisors is an integer number (1566833112000).

Almost surely, 2^{138239555279544} 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 138239555279544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (200554638336000).

138239555279544 is an abundant number, since it is smaller than the sum of its proper divisors (262869721392456).

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

138239555279544 is a wasteful number, since it uses less digits than its factorization.

138239555279544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 321915 (or 321905 counting only the distinct ones).

The product of its digits is 1632960000, while the sum is 72.

The spelling of 138239555279544 in words is "one hundred thirty-eight trillion, two hundred thirty-nine billion, five hundred fifty-five million, two hundred seventy-nine thousand, five hundred forty-four".