231322212 has 72 divisors (see below), whose sum is σ = 659917440. Its totient is φ = 67677120.

The previous prime is 231322211. The next prime is 231322229. The reversal of 231322212 is 212223132.

231322212 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 not an unprimeable number, because it can be changed into a prime (231322211) 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, 1413 + ... + 21555.

It is an arithmetic number, because the mean of its divisors is an integer number (9165520).

Almost surely, 2^231322212 is an apocalyptic number.

231322212 is a gapful number since it is divisible by the number (22) 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 231322212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (329958720).

231322212 is an abundant number, since it is smaller than the sum of its proper divisors (428595228).

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

231322212 is a wasteful number, since it uses less digits than its factorization.

231322212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20193 (or 20188 counting only the distinct ones).

The product of its digits is 288, while the sum is 18.

The square root of 231322212 is about 15209.2804563530. The cubic root of 231322212 is about 613.8643965553.

Adding to 231322212 its reverse (212223132), we get a palindrome (443545344).

The spelling of 231322212 in words is "two hundred thirty-one million, three hundred twenty-two thousand, two hundred twelve".