138321216 has 224 divisors, whose sum is σ = 468172800. Its totient is φ = 39605760.

The previous prime is 138321191. The next prime is 138321229. The reversal of 138321216 is 612123831.

It is a happy number.

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

It is a nude number because it is divisible by every one of its digits and also a Zuckerman number because it is divisible by the product of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 138321216.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 360961 + ... + 361343.

Almost surely, 2^138321216 is an apocalyptic number.

138321216 is a gapful number since it is divisible by the number (16) 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 138321216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (234086400).

138321216 is an abundant number, since it is smaller than the sum of its proper divisors (329851584).

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

138321216 is a wasteful number, since it uses less digits than its factorization.

138321216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 434 (or 418 counting only the distinct ones).

The product of its digits is 1728, while the sum is 27.

The square root of 138321216 is about 11761.0040387715. The cubic root of 138321216 is about 517.1655642148.

The spelling of 138321216 in words is "one hundred thirty-eight million, three hundred twenty-one thousand, two hundred sixteen".