138805056 has 224 divisors, whose sum is σ = 454030080. Its totient is φ = 41306112.

The previous prime is 138805027. The next prime is 138805057. The reversal of 138805056 is 650508831.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 138805056.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138805057) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 831085 + ... + 831251.

It is an arithmetic number, because the mean of its divisors is an integer number (2026920).

Almost surely, 2^138805056 is an apocalyptic number.

138805056 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138805056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (227015040).

138805056 is an abundant number, since it is smaller than the sum of its proper divisors (315225024).

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

138805056 is a wasteful number, since it uses less digits than its factorization.

138805056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238 (or 222 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The square root of 138805056 is about 11781.5557546531. Note that the first 3 decimals coincide. The cubic root of 138805056 is about 517.7678680437.

The spelling of 138805056 in words is "one hundred thirty-eight million, eight hundred five thousand, fifty-six".