138928424 has 8 divisors (see below), whose sum is σ = 260490810. Its totient is φ = 69464208.

The previous prime is 138928409. The next prime is 138928499. The reversal of 138928424 is 424829831.

It can be written as a sum of positive squares in only one way, i.e., 94439524 + 44488900 = 9718^2 + 6670^2 .

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

It is a super-2 number, since 2×138928424² = 38602213990247552, which contains 22 as substring.

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, 8683019 + ... + 8683034.

Almost surely, 2^138928424 is an apocalyptic number.

It is an amenable number.

138928424 is a deficient number, since it is larger than the sum of its proper divisors (121562386).

138928424 is a wasteful number, since it uses less digits than its factorization.

138928424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17366059 (or 17366055 counting only the distinct ones).

The product of its digits is 110592, while the sum is 41.

The square root of 138928424 is about 11786.7902331381. The cubic root of 138928424 is about 517.9212175769.

The spelling of 138928424 in words is "one hundred thirty-eight million, nine hundred twenty-eight thousand, four hundred twenty-four".