225621557 has 4 divisors (see below), whose sum is σ = 257853216. Its totient is φ = 193389900.

The previous prime is 225621553. The next prime is 225621619. The reversal of 225621557 is 755126522.

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 225621557 - 2² = 225621553 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 (225621553) 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, 16115819 + ... + 16115832.

It is an arithmetic number, because the mean of its divisors is an integer number (64463304).

Almost surely, 2^225621557 is an apocalyptic number.

It is an amenable number.

225621557 is a deficient number, since it is larger than the sum of its proper divisors (32231659).

225621557 is an equidigital number, since it uses as much as digits as its factorization.

225621557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32231658.

The product of its digits is 42000, while the sum is 35.

The square root of 225621557 is about 15020.7042777627. The cubic root of 225621557 is about 608.7797491038.

The spelling of 225621557 in words is "two hundred twenty-five million, six hundred twenty-one thousand, five hundred fifty-seven".