221525530 has 16 divisors (see below), whose sum is σ = 405505440. Its totient is φ = 87108112.

The previous prime is 221525509. The next prime is 221525533. The reversal of 221525530 is 35525122.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 221525495 and 221525504.

It is not an unprimeable number, because it can be changed into a prime (221525533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 187144 + ... + 188323.

It is an arithmetic number, because the mean of its divisors is an integer number (25344090).

Almost surely, 2^221525530 is an apocalyptic number.

221525530 is a deficient number, since it is larger than the sum of its proper divisors (183979910).

221525530 is a wasteful number, since it uses less digits than its factorization.

221525530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 375533.

The product of its (nonzero) digits is 3000, while the sum is 25.

The square root of 221525530 is about 14883.7337385483. The cubic root of 221525530 is about 605.0732147353.

The spelling of 221525530 in words is "two hundred twenty-one million, five hundred twenty-five thousand, five hundred thirty".