138331028 has 24 divisors (see below), whose sum is σ = 266518560. Its totient is φ = 62298720.

The previous prime is 138331019. The next prime is 138331033. The reversal of 138331028 is 820133831.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9626 + ... + 19217.

It is an arithmetic number, because the mean of its divisors is an integer number (11104940).

Almost surely, 2^138331028 is an apocalyptic number.

It is an amenable number.

138331028 is a deficient number, since it is larger than the sum of its proper divisors (128187532).

138331028 is a wasteful number, since it uses less digits than its factorization.

138331028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28967 (or 28965 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 138331028 is about 11761.4211726305. The cubic root of 138331028 is about 517.1777925354.

Adding to 138331028 its reverse (820133831), we get a palindrome (958464859).

The spelling of 138331028 in words is "one hundred thirty-eight million, three hundred thirty-one thousand, twenty-eight".