231321212 has 24 divisors (see below), whose sum is σ = 425519136. Its totient is φ = 109818368.

The previous prime is 231321191. The next prime is 231321301. The reversal of 231321212 is 212123132.

It is a super-2 number, since 2×231321212² = 107019006242297888, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3428 + ... + 21780.

It is an arithmetic number, because the mean of its divisors is an integer number (17729964).

Almost surely, 2^231321212 is an apocalyptic number.

It is an amenable number.

231321212 is a deficient number, since it is larger than the sum of its proper divisors (194197924).

231321212 is a wasteful number, since it uses less digits than its factorization.

231321212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18517 (or 18515 counting only the distinct ones).

The product of its digits is 144, while the sum is 17.

The square root of 231321212 is about 15209.2475816524. The cubic root of 231321212 is about 613.8635119806.

Adding to 231321212 its reverse (212123132), we get a palindrome (443444344).

The spelling of 231321212 in words is "two hundred thirty-one million, three hundred twenty-one thousand, two hundred twelve".