138238560 has 144 divisors (see below), whose sum is σ = 499576896. Its totient is φ = 34689024.

The previous prime is 138238531. The next prime is 138238561. The reversal of 138238560 is 65832831.

138238560 is a `hidden beast` number, since 13 + 82 + 3 + 8 + 560 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138238561) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 21657 + ... + 27303.

It is an arithmetic number, because the mean of its divisors is an integer number (3469284).

Almost surely, 2^138238560 is an apocalyptic number.

138238560 is a gapful number since it is divisible by the number (10) 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 138238560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (249788448).

138238560 is an abundant number, since it is smaller than the sum of its proper divisors (361338336).

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

138238560 is a wasteful number, since it uses less digits than its factorization.

138238560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5685 (or 5674 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 138238560 is about 11757.4895279562. The cubic root of 138238560 is about 517.0625302392.

The spelling of 138238560 in words is "one hundred thirty-eight million, two hundred thirty-eight thousand, five hundred sixty".