225206321 has 2 divisors, whose sum is σ = 225206322. Its totient is φ = 225206320.

The previous prime is 225206299. The next prime is 225206329. The reversal of 225206321 is 123602522.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 170668096 + 54538225 = 13064^2 + 7385^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-225206321 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (225206329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 112603160 + 112603161.

It is an arithmetic number, because the mean of its divisors is an integer number (112603161).

Almost surely, 2^225206321 is an apocalyptic number.

It is an amenable number.

225206321 is a deficient number, since it is larger than the sum of its proper divisors (1).

225206321 is an equidigital number, since it uses as much as digits as its factorization.

225206321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 225206321 is about 15006.8757907834. The cubic root of 225206321 is about 608.4060517979.

Adding to 225206321 its reverse (123602522), we get a palindrome (348808843).

The spelling of 225206321 in words is "two hundred twenty-five million, two hundred six thousand, three hundred twenty-one".