138078432 has 96 divisors (see below), whose sum is σ = 407907360. Its totient is φ = 46002816.

The previous prime is 138078431. The next prime is 138078443. The reversal of 138078432 is 234870831.

It is a tau number, because it is divible by the number of its divisors (96).

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 (138078431) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 68998 + ... + 70970.

It is an arithmetic number, because the mean of its divisors is an integer number (4249035).

Almost surely, 2^138078432 is an apocalyptic number.

138078432 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 138078432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (203953680).

138078432 is an abundant number, since it is smaller than the sum of its proper divisors (269828928).

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

138078432 is an frugal number, since it uses more digits than its factorization.

138078432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2004 (or 1978 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 138078432 is about 11750.6779378894. The cubic root of 138078432 is about 516.8628074356.

The spelling of 138078432 in words is "one hundred thirty-eight million, seventy-eight thousand, four hundred thirty-two".