221530 has 8 divisors (see below), whose sum is σ = 398772. Its totient is φ = 88608.

The previous prime is 221509. The next prime is 221537. The reversal of 221530 is 35122.

221530 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 196249 + 25281 = 443^2 + 159^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a plaindrome in base 13.

It is a self number, because there is not a number n which added to its sum of digits gives 221530.

It is not an unprimeable number, because it can be changed into a prime (221537) 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, 11067 + ... + 11086.

2²²¹⁵³⁰ is an apocalyptic number.

221530 is a deficient number, since it is larger than the sum of its proper divisors (177242).

221530 is a wasteful number, since it uses less digits than its factorization.

221530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22160.

The product of its (nonzero) digits is 60, while the sum is 13.

The square root of 221530 is about 470.6697355896. The cubic root of 221530 is about 60.5077284483.

Adding to 221530 its reverse (35122), we get a palindrome (256652).

The spelling of 221530 in words is "two hundred twenty-one thousand, five hundred thirty".