224397521 has 4 divisors (see below), whose sum is σ = 229616112. Its totient is φ = 219178932.

The previous prime is 224397517. The next prime is 224397527. The reversal of 224397521 is 125793422.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 125793422 = 2 ⋅62896711.

It is a cyclic number.

It is not a de Polignac number, because 224397521 - 2² = 224397517 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (224397527) 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, 2609231 + ... + 2609316.

It is an arithmetic number, because the mean of its divisors is an integer number (57404028).

Almost surely, 2^224397521 is an apocalyptic number.

It is an amenable number.

224397521 is a deficient number, since it is larger than the sum of its proper divisors (5218591).

224397521 is an equidigital number, since it uses as much as digits as its factorization.

224397521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5218590.

The product of its digits is 30240, while the sum is 35.

The square root of 224397521 is about 14979.9039048987. The cubic root of 224397521 is about 607.6768403645.

The spelling of 224397521 in words is "two hundred twenty-four million, three hundred ninety-seven thousand, five hundred twenty-one".