225545661 has 32 divisors (see below), whose sum is σ = 368323200. Its totient is φ = 135267840.

The previous prime is 225545657. The next prime is 225545693. The reversal of 225545661 is 166545522.

It is not a de Polignac number, because 225545661 - 2² = 225545657 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (225545641) 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 31 ways as a sum of consecutive naturals, for example, 24895 + ... + 32723.

It is an arithmetic number, because the mean of its divisors is an integer number (11510100).

Almost surely, 2^225545661 is an apocalyptic number.

It is an amenable number.

225545661 is a deficient number, since it is larger than the sum of its proper divisors (142777539).

225545661 is a wasteful number, since it uses less digits than its factorization.

225545661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7946 (or 7940 counting only the distinct ones).

The product of its digits is 72000, while the sum is 36.

The square root of 225545661 is about 15018.1776857247. The cubic root of 225545661 is about 608.7114797265.

The spelling of 225545661 in words is "two hundred twenty-five million, five hundred forty-five thousand, six hundred sixty-one".