138210028 has 48 divisors (see below), whose sum is σ = 286755840. Its totient is φ = 57585600.

The previous prime is 138210011. The next prime is 138210031. The reversal of 138210028 is 820012831.

It is a junction number, because it is equal to n+sod(n) for n = 138209984 and 138210011.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23250 + ... + 28582.

It is an arithmetic number, because the mean of its divisors is an integer number (5974080).

Almost surely, 2^138210028 is an apocalyptic number.

It is an amenable number.

138210028 is an abundant number, since it is smaller than the sum of its proper divisors (148545812).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

138210028 is a wasteful number, since it uses less digits than its factorization.

138210028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5398 (or 5396 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 138210028 is about 11756.2761110821. The cubic root of 138210028 is about 517.0269544365.

Adding to 138210028 its reverse (820012831), we get a palindrome (958222859).

The spelling of 138210028 in words is "one hundred thirty-eight million, two hundred ten thousand, twenty-eight".