225144221 has 2 divisors, whose sum is σ = 225144222. Its totient is φ = 225144220.

The previous prime is 225144163. The next prime is 225144307. The reversal of 225144221 is 122441522.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 193627225 + 31516996 = 13915^2 + 5614^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-225144221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (225140221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 112572110 + 112572111.

It is an arithmetic number, because the mean of its divisors is an integer number (112572111).

Almost surely, 2^225144221 is an apocalyptic number.

It is an amenable number.

225144221 is a deficient number, since it is larger than the sum of its proper divisors (1).

225144221 is an equidigital number, since it uses as much as digits as its factorization.

225144221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1280, while the sum is 23.

The square root of 225144221 is about 15004.8065965543. The cubic root of 225144221 is about 608.3501245798.

Adding to 225144221 its reverse (122441522), we get a palindrome (347585743).

The spelling of 225144221 in words is "two hundred twenty-five million, one hundred forty-four thousand, two hundred twenty-one".