138819445 has 4 divisors (see below), whose sum is σ = 166583340. Its totient is φ = 111055552.

The previous prime is 138819427. The next prime is 138819451. The reversal of 138819445 is 544918831.

138819445 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 544918831 = 8269 ⋅65899.

It can be written as a sum of positive squares in 2 ways, for example, as 43112356 + 95707089 = 6566^2 + 9783^2 .

It is a cyclic number.

It is not a de Polignac number, because 138819445 - 2¹⁵ = 138786677 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13881940 + ... + 13881949.

It is an arithmetic number, because the mean of its divisors is an integer number (41645835).

Almost surely, 2^138819445 is an apocalyptic number.

It is an amenable number.

138819445 is a deficient number, since it is larger than the sum of its proper divisors (27763895).

138819445 is an equidigital number, since it uses as much as digits as its factorization.

138819445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27763894.

The product of its digits is 138240, while the sum is 43.

The square root of 138819445 is about 11782.1663967201. The cubic root of 138819445 is about 517.7857586130.

The spelling of 138819445 in words is "one hundred thirty-eight million, eight hundred nineteen thousand, four hundred forty-five".