138305544 has 128 divisors (see below), whose sum is σ = 389558400. Its totient is φ = 40884480.

The previous prime is 138305533. The next prime is 138305549. The reversal of 138305544 is 445503831.

It is a super-2 number, since 2×138305544² = 38256847002271872, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138305549) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2267274 + ... + 2267334.

It is an arithmetic number, because the mean of its divisors is an integer number (3043425).

Almost surely, 2^138305544 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 138305544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (194779200).

138305544 is an abundant number, since it is smaller than the sum of its proper divisors (251252856).

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

138305544 is a wasteful number, since it uses less digits than its factorization.

138305544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152 (or 122 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 33.

The square root of 138305544 is about 11760.3377502519. The cubic root of 138305544 is about 517.1460316006.

The spelling of 138305544 in words is "one hundred thirty-eight million, three hundred five thousand, five hundred forty-four".