225556209 has 6 divisors (see below), whose sum is σ = 325803426. Its totient is φ = 150370800.

The previous prime is 225556157. The next prime is 225556213. The reversal of 225556209 is 902655522.

225556209 is a `hidden beast` number, since 2 + 25 + 5 + 5 + 620 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 136819809 + 88736400 = 11697^2 + 9420^2 .

It is not a de Polignac number, because 225556209 - 2⁷ = 225556081 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (225556259) 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 in 5 ways as a sum of consecutive naturals, for example, 12530892 + ... + 12530909.

It is an arithmetic number, because the mean of its divisors is an integer number (54300571).

Almost surely, 2^225556209 is an apocalyptic number.

It is an amenable number.

225556209 is a deficient number, since it is larger than the sum of its proper divisors (100247217).

225556209 is a wasteful number, since it uses less digits than its factorization.

225556209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25061807 (or 25061804 counting only the distinct ones).

The product of its (nonzero) digits is 54000, while the sum is 36.

The square root of 225556209 is about 15018.5288560498. The cubic root of 225556209 is about 608.7209686973.

The spelling of 225556209 in words is "two hundred twenty-five million, five hundred fifty-six thousand, two hundred nine".