231220213 has 16 divisors (see below), whose sum is σ = 285755904. Its totient is φ = 182557440.

The previous prime is 231220193. The next prime is 231220217. The reversal of 231220213 is 312022132.

It is a cyclic number.

It is not a de Polignac number, because 231220213 - 2⁹ = 231219701 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231220217) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15078 + ... + 26263.

It is an arithmetic number, because the mean of its divisors is an integer number (17859744).

Almost surely, 2^231220213 is an apocalyptic number.

It is an amenable number.

231220213 is a deficient number, since it is larger than the sum of its proper divisors (54535691).

231220213 is a wasteful number, since it uses less digits than its factorization.

231220213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41412.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 231220213 is about 15205.9269036781. The cubic root of 231220213 is about 613.7741576929.

Adding to 231220213 its reverse (312022132), we get a palindrome (543242345).

The spelling of 231220213 in words is "two hundred thirty-one million, two hundred twenty thousand, two hundred thirteen".