231211212 has 24 divisors (see below), whose sum is σ = 540862896. Its totient is φ = 76874688.

The previous prime is 231211193. The next prime is 231211219. The reversal of 231211212 is 212112132.

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

It is a junction number, because it is equal to n+sod(n) for n = 231211191 and 231211200.

It is not an unprimeable number, because it can be changed into a prime (231211219) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19503 + ... + 29030.

It is an arithmetic number, because the mean of its divisors is an integer number (22535954).

Almost surely, 2^231211212 is an apocalyptic number.

It is an amenable number.

231211212 is an abundant number, since it is smaller than the sum of its proper divisors (309651684).

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

231211212 is a wasteful number, since it uses less digits than its factorization.

231211212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48937 (or 48935 counting only the distinct ones).

The product of its digits is 48, while the sum is 15.

The square root of 231211212 is about 15205.6309306783. The cubic root of 231211212 is about 613.7661932034.

Adding to 231211212 its reverse (212112132), we get a palindrome (443323344).

The spelling of 231211212 in words is "two hundred thirty-one million, two hundred eleven thousand, two hundred twelve".