221310317 has 2 divisors, whose sum is σ = 221310318. Its totient is φ = 221310316.

The previous prime is 221310307. The next prime is 221310343. The reversal of 221310317 is 713013122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 124858276 + 96452041 = 11174^2 + 9821^2 .

It is a cyclic number.

It is not a de Polignac number, because 221310317 - 2²² = 217116013 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 (221310307) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110655158 + 110655159.

It is an arithmetic number, because the mean of its divisors is an integer number (110655159).

Almost surely, 2^221310317 is an apocalyptic number.

It is an amenable number.

221310317 is a deficient number, since it is larger than the sum of its proper divisors (1).

221310317 is an equidigital number, since it uses as much as digits as its factorization.

221310317 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 252, while the sum is 20.

The square root of 221310317 is about 14876.5021762510. The cubic root of 221310317 is about 604.8772075089.

Adding to 221310317 its reverse (713013122), we get a palindrome (934323439).

The spelling of 221310317 in words is "two hundred twenty-one million, three hundred ten thousand, three hundred seventeen".