225213661 has 4 divisors (see below), whose sum is σ = 230451232. Its totient is φ = 219976092.

The previous prime is 225213629. The next prime is 225213701. The reversal of 225213661 is 166312522.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 225213661 - 2⁵ = 225213629 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (225213761) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2618721 + ... + 2618806.

It is an arithmetic number, because the mean of its divisors is an integer number (57612808).

Almost surely, 2^225213661 is an apocalyptic number.

It is an amenable number.

225213661 is a deficient number, since it is larger than the sum of its proper divisors (5237571).

225213661 is an equidigital number, since it uses as much as digits as its factorization.

225213661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5237570.

The product of its digits is 4320, while the sum is 28.

The square root of 225213661 is about 15007.1203433570. The cubic root of 225213661 is about 608.4126615175.

The spelling of 225213661 in words is "two hundred twenty-five million, two hundred thirteen thousand, six hundred sixty-one".