138440232 has 256 divisors, whose sum is σ = 476160000. Its totient is φ = 36391680.

The previous prime is 138440227. The next prime is 138440233. The reversal of 138440232 is 232044831.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 138440196 and 138440205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138440233) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1752369 + ... + 1752447.

It is an arithmetic number, because the mean of its divisors is an integer number (1860000).

Almost surely, 2^138440232 is an apocalyptic number.

138440232 is a gapful number since it is divisible by the number (12) 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 138440232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (238080000).

138440232 is an abundant number, since it is smaller than the sum of its proper divisors (337719768).

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

138440232 is a wasteful number, since it uses less digits than its factorization.

138440232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 181 (or 171 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

The square root of 138440232 is about 11766.0627229333. The cubic root of 138440232 is about 517.3138502925.

It can be divided in two parts, 1384 and 40232, that added together give a triangular number (41616 = T₂₈₈).

The spelling of 138440232 in words is "one hundred thirty-eight million, four hundred forty thousand, two hundred thirty-two".