171234221 has 2 divisors, whose sum is σ = 171234222. Its totient is φ = 171234220.

The previous prime is 171234191. The next prime is 171234223. The reversal of 171234221 is 122432171.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 158886025 + 12348196 = 12605^2 + 3514^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-171234221 is a prime.

It is a Sophie Germain prime.

Together with 171234223, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (171234223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 85617110 + 85617111.

It is an arithmetic number, because the mean of its divisors is an integer number (85617111).

Almost surely, 2^171234221 is an apocalyptic number.

It is an amenable number.

171234221 is a deficient number, since it is larger than the sum of its proper divisors (1).

171234221 is an equidigital number, since it uses as much as digits as its factorization.

171234221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 672, while the sum is 23.

The square root of 171234221 is about 13085.6494298143. The cubic root of 171234221 is about 555.3032144509.

Adding to 171234221 its reverse (122432171), we get a palindrome (293666392).

The spelling of 171234221 in words is "one hundred seventy-one million, two hundred thirty-four thousand, two hundred twenty-one".