225249521 has 18 divisors (see below), whose sum is σ = 267847218. Its totient is φ = 188872320.

The previous prime is 225249517. The next prime is 225249527. The reversal of 225249521 is 125942522.

225249521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 181953121 + 43296400 = 13489^2 + 6580^2 .

It is not a de Polignac number, because 225249521 - 2² = 225249517 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (225249527) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 107201 + ... + 109281.

It is an arithmetic number, because the mean of its divisors is an integer number (14880401).

Almost surely, 2^225249521 is an apocalyptic number.

It is an amenable number.

225249521 is a deficient number, since it is larger than the sum of its proper divisors (42597697).

225249521 is an equidigital number, since it uses as much as digits as its factorization.

225249521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2189 (or 2135 counting only the distinct ones).

The product of its digits is 14400, while the sum is 32.

The square root of 225249521 is about 15008.3150619915. The cubic root of 225249521 is about 608.4449516253. Note that the first 3 decimals are identical.

The spelling of 225249521 in words is "two hundred twenty-five million, two hundred forty-nine thousand, five hundred twenty-one".