138438072 has 192 divisors, whose sum is σ = 424569600. Its totient is φ = 42094080.

The previous prime is 138438061. The next prime is 138438073. The reversal of 138438072 is 270834831.

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 (138438073) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1949797 + ... + 1949867.

It is an arithmetic number, because the mean of its divisors is an integer number (2211300).

Almost surely, 2^138438072 is an apocalyptic number.

138438072 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 138438072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (212284800).

138438072 is an abundant number, since it is smaller than the sum of its proper divisors (286131528).

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

138438072 is a wasteful number, since it uses less digits than its factorization.

138438072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168 (or 152 counting only the distinct ones).

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

The square root of 138438072 is about 11765.9709331614. The cubic root of 138438072 is about 517.3111598325.

The spelling of 138438072 in words is "one hundred thirty-eight million, four hundred thirty-eight thousand, seventy-two".