231344221 has 2 divisors, whose sum is σ = 231344222. Its totient is φ = 231344220.

The previous prime is 231344203. The next prime is 231344249. The reversal of 231344221 is 122443132.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 231344100 + 121 = 15210^2 + 11^2 .

It is a cyclic number.

It is not a de Polignac number, because 231344221 - 2⁷ = 231344093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 231344192 and 231344201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231344261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115672110 + 115672111.

It is an arithmetic number, because the mean of its divisors is an integer number (115672111).

Almost surely, 2^231344221 is an apocalyptic number.

It is an amenable number.

231344221 is a deficient number, since it is larger than the sum of its proper divisors (1).

231344221 is an equidigital number, since it uses as much as digits as its factorization.

231344221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1152, while the sum is 22.

The square root of 231344221 is about 15210.0039776458. The cubic root of 231344221 is about 613.8838645129.

Adding to 231344221 its reverse (122443132), we get a palindrome (353787353).

The spelling of 231344221 in words is "two hundred thirty-one million, three hundred forty-four thousand, two hundred twenty-one".