138724328 has 8 divisors (see below), whose sum is σ = 260108130. Its totient is φ = 69362160.

The previous prime is 138724319. The next prime is 138724331. The reversal of 138724328 is 823427831.

It can be written as a sum of positive squares in only one way, i.e., 134050084 + 4674244 = 11578^2 + 2162^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 138724291 and 138724300.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8670263 + ... + 8670278.

Almost surely, 2^138724328 is an apocalyptic number.

It is an amenable number.

138724328 is a deficient number, since it is larger than the sum of its proper divisors (121383802).

138724328 is a wasteful number, since it uses less digits than its factorization.

138724328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17340547 (or 17340543 counting only the distinct ones).

The product of its digits is 64512, while the sum is 38.

The square root of 138724328 is about 11778.1292232680. The cubic root of 138724328 is about 517.6674719162.

The spelling of 138724328 in words is "one hundred thirty-eight million, seven hundred twenty-four thousand, three hundred twenty-eight".