225721225 has 12 divisors (see below), whose sum is σ = 280092316. Its totient is φ = 180449280.

The previous prime is 225721219. The next prime is 225721247. The reversal of 225721225 is 522127522.

It can be written as a sum of positive squares in 6 ways, for example, as 80084601 + 145636624 = 8949^2 + 12068^2 .

It is not a de Polignac number, because 225721225 - 2³ = 225721217 is a prime.

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 225721193 and 225721202.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 50689 + ... + 54961.

Almost surely, 2^225721225 is an apocalyptic number.

225721225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

225721225 is a deficient number, since it is larger than the sum of its proper divisors (54371091).

225721225 is a wasteful number, since it uses less digits than its factorization.

225721225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6396 (or 6391 counting only the distinct ones).

The product of its digits is 5600, while the sum is 28.

The square root of 225721225 is about 15024.0215987598. The cubic root of 225721225 is about 608.8693784349.

Adding to 225721225 its reverse (522127522), we get a palindrome (747848747).

The spelling of 225721225 in words is "two hundred twenty-five million, seven hundred twenty-one thousand, two hundred twenty-five".