138305256 has 64 divisors (see below), whose sum is σ = 379814400. Its totient is φ = 41773248.

The previous prime is 138305203. The next prime is 138305261. The reversal of 138305256 is 652503831.

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, 3895 + ... + 17081.

It is an arithmetic number, because the mean of its divisors is an integer number (5934600).

Almost surely, 2^138305256 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138305256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (189907200).

138305256 is an abundant number, since it is smaller than the sum of its proper divisors (241509144).

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

138305256 is a wasteful number, since it uses less digits than its factorization.

138305256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13238 (or 13234 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 33.

The square root of 138305256 is about 11760.3255056992. The cubic root of 138305256 is about 517.1456726413.

The spelling of 138305256 in words is "one hundred thirty-eight million, three hundred five thousand, two hundred fifty-six".