138784561444 has 27 divisors (see below), whose sum is σ = 258023568243. Its totient is φ = 65304421248.

The previous prime is 138784561379. The next prime is 138784561451. The reversal of 138784561444 is 444165487831.

It is a happy number.

The square root of 138784561444 is 372538.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 22994083044 + 115790478400 = 151638^2 + 340280^2 .

It is a super-2 number, since 2×138784561444² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 12660814 + ... + 12671770.

Almost surely, 2^138784561444 is an apocalyptic number.

138784561444 is the 372538-th square number.

It is an amenable number.

138784561444 is a deficient number, since it is larger than the sum of its proper divisors (119239006799).

138784561444 is an frugal number, since it uses more digits than its factorization.

138784561444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21952 (or 10976 counting only the distinct ones).

The product of its digits is 10321920, while the sum is 55.

The spelling of 138784561444 in words is "one hundred thirty-eight billion, seven hundred eighty-four million, five hundred sixty-one thousand, four hundred forty-four".