123231312 has 120 divisors (see below), whose sum is σ = 359266440. Its totient is φ = 39398400.

The previous prime is 123231299. The next prime is 123231313. The reversal of 123231312 is 213132321.

123231312 is a `hidden beast` number, since 123 + 231 + 312 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 104775696 + 18455616 = 10236^2 + 4296^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123231313) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 538014 + ... + 538242.

It is an arithmetic number, because the mean of its divisors is an integer number (2993887).

Almost surely, 2^123231312 is an apocalyptic number.

123231312 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 123231312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (179633220).

123231312 is an abundant number, since it is smaller than the sum of its proper divisors (236035128).

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

123231312 is a wasteful number, since it uses less digits than its factorization.

123231312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 381 (or 372 counting only the distinct ones).

The product of its digits is 216, while the sum is 18.

The square root of 123231312 is about 11100.9599584901. The cubic root of 123231312 is about 497.6305383738.

Adding to 123231312 its reverse (213132321), we get a palindrome (336363633).

The spelling of 123231312 in words is "one hundred twenty-three million, two hundred thirty-one thousand, three hundred twelve".