221325217 has 2 divisors, whose sum is σ = 221325218. Its totient is φ = 221325216.

The previous prime is 221325199. The next prime is 221325241. The reversal of 221325217 is 712523122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 174662656 + 46662561 = 13216^2 + 6831^2 .

It is a cyclic number.

It is not a de Polignac number, because 221325217 - 2¹¹ = 221323169 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221325191 and 221325200.

It is not a weakly prime, because it can be changed into another prime (221325287) 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, 110662608 + 110662609.

It is an arithmetic number, because the mean of its divisors is an integer number (110662609).

Almost surely, 2^221325217 is an apocalyptic number.

It is an amenable number.

221325217 is a deficient number, since it is larger than the sum of its proper divisors (1).

221325217 is an equidigital number, since it uses as much as digits as its factorization.

221325217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1680, while the sum is 25.

The square root of 221325217 is about 14877.0029575852. The cubic root of 221325217 is about 604.8907819146.

Adding to 221325217 its reverse (712523122), we get a palindrome (933848339).

The spelling of 221325217 in words is "two hundred twenty-one million, three hundred twenty-five thousand, two hundred seventeen".