225399221 has 2 divisors, whose sum is σ = 225399222. Its totient is φ = 225399220.

The previous prime is 225399217. The next prime is 225399269. The reversal of 225399221 is 122993522.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 224580196 + 819025 = 14986^2 + 905^2 .

It is a cyclic number.

It is not a de Polignac number, because 225399221 - 2² = 225399217 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (225399211) 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, 112699610 + 112699611.

It is an arithmetic number, because the mean of its divisors is an integer number (112699611).

Almost surely, 2^225399221 is an apocalyptic number.

It is an amenable number.

225399221 is a deficient number, since it is larger than the sum of its proper divisors (1).

225399221 is an equidigital number, since it uses as much as digits as its factorization.

225399221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 19440, while the sum is 35.

The square root of 225399221 is about 15013.3014690307. The cubic root of 225399221 is about 608.5797118654.

The spelling of 225399221 in words is "two hundred twenty-five million, three hundred ninety-nine thousand, two hundred twenty-one".