8688221 has 2 divisors, whose sum is σ = 8688222. Its totient is φ = 8688220.

The previous prime is 8688209. The next prime is 8688259. The reversal of 8688221 is 1228868.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7562500 + 1125721 = 2750^2 + 1061^2 .

It is a cyclic number.

It is not a de Polignac number, because 8688221 - 2⁶ = 8688157 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8688271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4344110 + 4344111.

It is an arithmetic number, because the mean of its divisors is an integer number (4344111).

Almost surely, 2^8688221 is an apocalyptic number.

It is an amenable number.

8688221 is a deficient number, since it is larger than the sum of its proper divisors (1).

8688221 is an equidigital number, since it uses as much as digits as its factorization.

8688221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12288, while the sum is 35.

The square root of 8688221 is about 2947.5788369440. The cubic root of 8688221 is about 205.5781498200.

The spelling of 8688221 in words is "eight million, six hundred eighty-eight thousand, two hundred twenty-one".