231143044221 has 6 divisors (see below), whose sum is σ = 333873286110. Its totient is φ = 154095362808.

The previous prime is 231143044207. The next prime is 231143044243. The reversal of 231143044221 is 122440341132.

231143044221 is a `hidden beast` number, since 2 + 3 + 1 + 1 + 430 + 4 + 4 + 221 = 666.

It can be written as a sum of positive squares in only one way, i.e., 175612121721 + 55530922500 = 419061^2 + 235650^2 .

It is not a de Polignac number, because 231143044221 - 2⁹ = 231143043709 is a prime.

It is a super-2 number, since 2×231143044221² (a number of 24 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231143044921) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12841280226 + ... + 12841280243.

It is an arithmetic number, because the mean of its divisors is an integer number (55645547685).

Almost surely, 2^231143044221 is an apocalyptic number.

It is an amenable number.

231143044221 is a deficient number, since it is larger than the sum of its proper divisors (102730241889).

231143044221 is a wasteful number, since it uses less digits than its factorization.

231143044221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25682560475 (or 25682560472 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

Adding to 231143044221 its reverse (122440341132), we get a palindrome (353583385353).

The spelling of 231143044221 in words is "two hundred thirty-one billion, one hundred forty-three million, forty-four thousand, two hundred twenty-one".