221530273 has 4 divisors (see below), whose sum is σ = 231162048. Its totient is φ = 211898500.

The previous prime is 221530271. The next prime is 221530307. The reversal of 221530273 is 372035122.

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 221530273 - 2¹ = 221530271 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221530271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4815853 + ... + 4815898.

It is an arithmetic number, because the mean of its divisors is an integer number (57790512).

Almost surely, 2^221530273 is an apocalyptic number.

221530273 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

221530273 is a deficient number, since it is larger than the sum of its proper divisors (9631775).

221530273 is an equidigital number, since it uses as much as digits as its factorization.

221530273 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9631774.

The product of its (nonzero) digits is 2520, while the sum is 25.

The square root of 221530273 is about 14883.8930727145. The cubic root of 221530273 is about 605.0775330364.

Adding to 221530273 its reverse (372035122), we get a palindrome (593565395).

The spelling of 221530273 in words is "two hundred twenty-one million, five hundred thirty thousand, two hundred seventy-three".