231244221 has 24 divisors (see below), whose sum is σ = 344660736. Its totient is φ = 137704320.

The previous prime is 231244207. The next prime is 231244243. The reversal of 231244221 is 122442132.

231244221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 231244221 - 2⁶ = 231244157 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231244261) 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, 8361 + ... + 23073.

It is an arithmetic number, because the mean of its divisors is an integer number (14360864).

Almost surely, 2^231244221 is an apocalyptic number.

It is an amenable number.

231244221 is a deficient number, since it is larger than the sum of its proper divisors (113416515).

231244221 is a wasteful number, since it uses less digits than its factorization.

231244221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14773 (or 14760 counting only the distinct ones).

The product of its digits is 768, while the sum is 21.

The square root of 231244221 is about 15206.7163122089. The cubic root of 231244221 is about 613.7954000399.

Adding to 231244221 its reverse (122442132), we get a palindrome (353686353).

The spelling of 231244221 in words is "two hundred thirty-one million, two hundred forty-four thousand, two hundred twenty-one".