231275221 has 12 divisors (see below), whose sum is σ = 243086400. Its totient is φ = 219967320.

The previous prime is 231275183. The next prime is 231275227. The reversal of 231275221 is 122572132.

It is a de Polignac number, because none of the positive numbers 2^k-231275221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231275227) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 54660 + ... + 58738.

It is an arithmetic number, because the mean of its divisors is an integer number (20257200).

Almost surely, 2^231275221 is an apocalyptic number.

It is an amenable number.

231275221 is a deficient number, since it is larger than the sum of its proper divisors (11811179).

231275221 is an equidigital number, since it uses as much as digits as its factorization.

231275221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4200 (or 4169 counting only the distinct ones).

The product of its digits is 1680, while the sum is 25.

The square root of 231275221 is about 15207.7355645080. The cubic root of 231275221 is about 613.8228267537.

The spelling of 231275221 in words is "two hundred thirty-one million, two hundred seventy-five thousand, two hundred twenty-one".