8231727221 has 2 divisors, whose sum is σ = 8231727222. Its totient is φ = 8231727220.

The previous prime is 8231727191. The next prime is 8231727223. The reversal of 8231727221 is 1227271328.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7243882321 + 987844900 = 85111^2 + 31430^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8231727221 is a prime.

It is a super-2 number, since 2×8231727221² (a number of 21 digits) contains 22 as substring.

Together with 8231727223, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8231727223) 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 as a sum of consecutive naturals, namely, 4115863610 + 4115863611.

It is an arithmetic number, because the mean of its divisors is an integer number (4115863611).

Almost surely, 2^8231727221 is an apocalyptic number.

It is an amenable number.

8231727221 is a deficient number, since it is larger than the sum of its proper divisors (1).

8231727221 is an equidigital number, since it uses as much as digits as its factorization.

8231727221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18816, while the sum is 35.

The square root of 8231727221 is about 90728.8665254890. The cubic root of 8231727221 is about 2019.1270957240.

Adding to 8231727221 its reverse (1227271328), we get a palindrome (9458998549).

The spelling of 8231727221 in words is "eight billion, two hundred thirty-one million, seven hundred twenty-seven thousand, two hundred twenty-one".