138656 has 24 divisors (see below), whose sum is σ = 312480. Its totient is φ = 59328.

The previous prime is 138647. The next prime is 138661. The reversal of 138656 is 656831.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86 + ... + 533.

It is an arithmetic number, because the mean of its divisors is an integer number (13020).

2¹³⁸⁶⁵⁶ is an apocalyptic number.

138656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

138656 is an abundant number, since it is smaller than the sum of its proper divisors (173824).

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

138656 is an equidigital number, since it uses as much as digits as its factorization.

138656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 636 (or 628 counting only the distinct ones).

The product of its digits is 4320, while the sum is 29.

The square root of 138656 is about 372.3654119276. The cubic root of 138656 is about 51.7582466418.

The spelling of 138656 in words is "one hundred thirty-eight thousand, six hundred fifty-six".