123216 has 40 divisors (see below), whose sum is σ = 339264. Its totient is φ = 38400.

The previous prime is 123209. The next prime is 123217. The reversal of 123216 is 612321.

It is a nude number because it is divisible by every one of its digits.

It is an alternating number because its digits alternate between odd and even.

It is a junction number, because it is equal to n+sod(n) for n = 123195 and 123204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123217) by changing a digit.

123216 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 741 + ... + 891.

2¹²³²¹⁶ is an apocalyptic number.

123216 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 123216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (169632).

123216 is an abundant number, since it is smaller than the sum of its proper divisors (216048).

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

123216 is a wasteful number, since it uses less digits than its factorization.

123216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179 (or 173 counting only the distinct ones).

The product of its digits is 72, while the sum is 15.

The square root of 123216 is about 351.0213668710. The cubic root of 123216 is about 49.7609926636.

Subtracting from 123216 its sum of digits (15), we obtain a square (123201 = 351²).

Adding to 123216 its reverse (612321), we get a palindrome (735537).

The spelling of 123216 in words is "one hundred twenty-three thousand, two hundred sixteen".